LTC3130/LTC3130-1
25V, 600mA Buck-Boost
DC/DC Converter with
1.6µA Quiescent Current
DESCRIPTIONFEATURES
Regulates VOUT Above, Below or Equal to VIN
Wide VIN Range: 2.4V to 25V,
<1V to 25V (Using EXTVCC Input)
nn V
OUT Range: 1V to 25V
nn Adjustable Output Voltage (LTC®3130)
nn Four Selectable Fixed Output Voltages (LTC3130-1)
nn 1.2µA No-Load Input Current in Burst Mode®
Operation (VIN = 12V, VOUT = 5V)
nn 600mA Output Current in Buck Modenn Pin-Selectable 850mA/450mA Current Limit (LTC3130)
nn Up to 95% Efficiency
nn Pin-Selectable Burst Mode Operation
nn 1.2MHz Ultralow Noise PWM Frequency
nn Accurate RUN Pin Threshold
nn Power Good Indicator
nn Programmable Maximum Power Point Control
nn I = 500nA in ShutdownQ
nn Thermally-Enhanced 20-Lead 3mm × 4mm QFN and
16-Lead MSOP Packages
nnnn

APPLICATIONSThe LTC3130/LTC3130-1 are high efficiency, low noise,
600mA buck-boost converters with wide VIN and VOUT
ranges. For high efficiency operation at light loads,
Burst Mode operation can be selected, reducing the quiescent current to just 1.6µA. Converter start-up is achieved
from sources as low as 7.5µW.
The LTC3130/LTC3130-1 employ an ultralow noise, 1.2MHz
PWM architecture that minimizes solution footprint by
allowing the use of tiny, low profile inductors and ceramic
capacitors. Built-in loop compensation and soft-start
reduces external parts count and simplifies the design.
Features include an accurate RUN comparator threshold toallow predictable regulator turn-on and a maximum power
point control (MPPC) capability that ensures maximum
power extraction from non-ideal sources such as photovoltaic panels. The LTC3130-1 includes an internal voltage
divider to provide four selectable fixed output voltages.
Additional features include a power good output, an external
VCC input and thermal shutdown.
The LTC3130 and LTC3130-1 are available in thermallyenhanced 20-lead 3mm × 4mm QFN and 16-lead MSOP
packages.

Long-Life, Battery-Operated Instruments
Portable Military Radios
nn Low Power Sensors
nn Solar Panel Post-Regulator/Chargernn
nn

L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
and PowerPath is a trademark of Linear Technology Corporation. All other trademarks are theproperty of their respective owners.

TYPICAL APPLICATION
22nF

22nF

6.8µH

90

10µF

BST1
PVIN
VIN
RUN

VCC

SW1

SW2

LTC3130-1

BST2
VOUT

VOUT
12V
10µF 600mA

EXTVCC

MPPC
MODE

PGOOD

EFFICIENCY (%)

80

VIN
4 Li-Ion+

Efficiency vs Load
100

70
60
50
40
30
20

VS1
VS2

10

VCC
GND

PGND

4.7µF

0
0.01

3130 TA01a

VIN = 14.4V, VOUT = 12V
0.1

1
10
LOAD (mA)

100

800
3130 TA01b

3130f

For more information www.linear.com/LTC3130

1

LTC3130/LTC3130-1
ABSOLUTE MAXIMUM RATINGS (Notes 1, 8)
PVIN , VIN, VOUT Voltage..............................–0.3 to 27.5V
EXTVCC Voltage..........................................–0.3 to 27.5V
BST1, BST2 Voltage................ (SW – 0.3V) to (SW + 6V)
RUN, PGOOD Voltage..................................–0.3 to 27.5V
MODE, MPPC.................................................. –0.3 to 6V
VS1, VS2 Voltage (LTC3130-1)........................ –0.3 to 6V
ILIM, FB Voltage (LTC3130)............................ –0.3 to 6V
PGOOD Sink Current...............................................12mA

Operating Junction Temperature
Range (Notes 2, 5, 6).......................... –40°C to 125°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10sec)
MSE................................................................... 300°C

PIN CONFIGURATION
NC

PGND

PGND

SW1

TOP VIEW

20 19 18 17
BST1 1

16 BST2

PVIN 215 SW2VIN 3

14 VOUT

21
GND

RUN 4

TOP VIEW
GND 1
BST1 2SW1 3PVIN 4
VIN 5
RUN 6
VCC 7
MPPC 813 PGOOD
12 EXTVCC

VCC 5
9 10
VS2/FB

SW2
BST2
VOUT
PGOOD
EXTVCCMODE
VS1/ILIM
VS2/FBMSE PACKAGE
16-LEAD PLASTIC MSOP

VS1/ILIM

8GND

11 MODE7GND

MPPC 6

17
GND

16
15
14
13
12
11
10
9

TJMAX = 125°C, θJA = 40°C/W, θJC = 10°C/W (NOTE 6)EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCBUDC PACKAGE
20-LEAD (3mm × 4mm) PLASTIC QFNTJMAX = 125°C, θJA = 52°C/W, θJC = 6.8°C/W (NOTE 6)EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCBORDER INFORMATION http://www.linear.com/product/LTC3130#orderinfo
LEAD FREE FINISH

TAPE AND REEL

PACKAGE DESCRIPTIONTEMPERATURE RANGE

LTC3130EUDC#PBF

LTC3130EUDC#TRPBFPART MARKING*
LGTS

20-Lead (3mm × 4mm) Plastic QFN–40°C to 125°C

LTC3130EUDC-1#PBF

LTC3130EUDC-1#TRPBF

LGTT

20-Lead (3mm × 4mm) Plastic QFN–40°C to 125°C

LTC3130IUDC#PBF

LTC3130IUDC#TRPBF

LGTS

20-Lead (3mm × 4mm) Plastic QFN–40°C to 125°C

LTC3130IUDC-1#PBF

LTC3130IUDC-1#TRPBF

LGTT

20-Lead (3mm × 4mm) Plastic QFN–40°C to 125°C

LTC3130EMSE#PBF

LTC3130EMSE#TRPBF

3130

16-Lead Plastic MSOP

–40°C to 125°C

LTC3130EMSE-1#PBF

LTC3130EMSE-1#TRPBF

31301

16-Lead Plastic MSOP

–40°C to 125°C

LTC3130IMSE#PBF

LTC3130IMSE#TRPBF

3130

16-Lead Plastic MSOP

–40°C to 125°C

LTC3130IMSE-1#PBF

LTC3130IMSE-1#TRPBF

31301

16-Lead Plastic MSOP

–40°C to 125°C

Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping
container.For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/. Some packages are available in 500 unit reels throughdesignated sales channels with #TRMPBF suffix.

2

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
ELECTRICAL CHARACTERISTICS

The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at TA = 25°C (Note 2). PVIN = VIN = 12V, VOUT = 5V unless otherwise noted.
PARAMETER
VIN Start-Up Voltage
Input Voltage Range
Output Voltage Adjust Range (LTC3130)
Feedback Voltage (LTC3130)

CONDITIONSEXTVCC = 0V
EXTVCC > 3.15V, RUN > 1.1V
EXTVCC > 3.15V, RUN > 1.1V

MIN
l
l
l
l

For External FB Resistor Applications
From –40°C to +85°C (Note 3)
Feedback Input Current (LTC3130)
FB = 1.1V
VS1 = VS2 = 0V
Fixed VOUT Voltages (LTC3130-1)
VS1 = VCC, VS2 = 0V
VS1 = 0V, VS2 = VCC
VS1 = VS2 = VCC
VIN Quiescent Current – Shutdown
RUN < 0.2V
0.85V < RUN < 0.9V, EXTVCC = 0V
VIN Quiescent Current – UVLO
VIN Quiescent Current – Burst Mode Operation FB > 1.02V (LTC3130), VOUT > VREG (LTC3130-1),(Sleeping)
MODE = 0V, RUN = VIN, MPPC > 1.05V
SW1 = SW2 = 0V, VIN = VOUT = 25V
NMOS Switch Leakage on VIN and VOUTNMOS Switch On-Resistance
VCC = 4V
Inductor Average Current Limit
LTC3130-1 (Note 4), LTC3130: ILIM = VCC (Note 4)
LTC3130: ILIM = 0V (Note 4)
Inductor Peak Current Limit
LTC3130-1 (Note 4), LTC3130: ILIM = VCC (Note 4)
LTC3130: ILIM = 0V (Note 4)
Maximum Boost Duty Cycle
LTC3130-1: VOUT < VREG (Note 7),
LTC3130: FB < 0.975V (Note 7)(Percentage of Period SW2 is Low)
Minimum Duty Cycle
LTC3130-1: VOUT > VREG (Note 7),
LTC3130: FB > 1.02V (Note 7)
Switching Frequency
SW1 and SW2 Minimum Low Time
(Note 3)MPPC Reference Voltage
MPPC Input Current
MPPC = 5V
RUN Logic Threshold to Enable Reference
RUN Threshold to Enable Switching (Rising)
VIN > 2.4V or EXTVCC > 3.15V
RUN Threshold Hysteresis
RUN Input Current
RUN = 25V
RUN = 1V
ILIM Input Logic High(LTC3130)
ILIM Input Logic Low(LTC3130)
ILIM Input Current(LTC3130) ILIM = 5V
VS1, VS2 Input Logic High(LTC3130-1)
VS1, VS2 Input Logic Low(LTC3130-1)
VS1, VS2 Input Current(LTC3130-1) VS1, VS2 = 5V
MODE Input Logic HighMODE Input Logic Low
MODE Input Current
MODE = 5V (If RUN is Low or VCC is in UVLO)MODE = 5V (If Switching is Enabled)

l

l
l
l
l

l
l
l
l
l

0.6
1.0
0.975
0.980
1.75
3.20
4.85
11.64

660
250
0.9
0.6
91

TYP
2.30
0.6

1.000
1.000
0.1
1.80
3.3
5.0
12.0
500
1.4
1.6
5
0.35
850
450
1.3
0.85
94

l
l

1.00

l

0.95

l

l

0.2
1.01
90

l

1.1

l

1.20
70
1.00
1
0.6
1.05
100
1
0.1

100
1200
650
1.7
1.15
97

nA
Ω
mA
mA
A
A
%

0

%

1.40

MHz
ns
V
nA
V
V
mV
nA
nA
V
V
nA
V
V
nA
V
V
nA
µA

1.05
20
0.85
1.09
110
30
5
0.35
20

1

0.35
20

1
1.7

0.35
20
4

1.1

l

l

UNITS
V
V
V
V
V
V
nA
V
V
V
V
nA
µA
µA

1

l

l

MAX
2.40
1.0
25
25
1.020
1.020
10
1.85
3.39
5.125
12.30
850
2.4
2.7

1.1

l

3130f

For more information www.linear.com/LTC3130

3

LTC3130/LTC3130-1
ELECTRICAL CHARACTERISTICS

The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at TA = 25°C (Note 2). PVIN = VIN = 12V, VOUT = 5V unless otherwise noted.
PARAMETER
Soft-Start Time
VCC Voltage
VCC Voltage -– Shutdown
VCC Dropout Voltage (VIN – VCC)VCC Current Limit
VCC UVLO Threshold (Rising)
VCC UVLO Hysteresis
EXTVCC Enable Threshold
EXTVCC Enable Hysteresis
EXTVCC Input Operating Range
EXTVCC Quiescent Current – Burst Mode
Operation (Sleeping)
EXTVCC Quiescent Current – Shutdown
EXTVCC Current Limit
VIN Sleep Current When Powered by EXTVCCVOUT UV Threshold
VOUT UV Hysteresis
VOUT Quiescent Current – Shutdown

CONDITIONSFor Average Inductor Current to Reach Limit(EXTVCC or VIN) > 4.7V, RUN > 0.85V
RUN ≤ 0.2V
VIN = 3.0V, Switching
VCC = 0V

MIN

l

2.20
100
2.85

l

3.15

l

EXTVCC > 3.15V, FB >1.02V (LTC3130), MPPC > 1.05V
VOUT > VREG (LTC3130-1), MODE = 0V, RUN > 1.10V
EXTVCC = 5V, RUN < 0.2V
VCC = 0V, EXTVCC = 15V
FB > 1.02V (LTC3130), VOUT > VREG (LTC3130-1),
EXTVCC > 3.15V, MODE = 0V,
RUN >1.10V, VIN = 12V, MPPC > 1.05V
Rising

TYP
12
4
3.25
50
17
2.3
120
3.0
260
1.6

l

0.35

nA
mA
nA

0.7
55
(VOUT–1)

0.95

V
mV
µA

MODE = 0V, FB > 1.02V, MPPC > 1.05V

PGOOD Threshold, Rising
PGOOD Hysteresis
PGOOD Voltage Low
PGOOD Leakage

Referenced to Programmed VOUT Voltage
Referenced to Programmed VOUT Voltage
ISINK = 1mA
PGOOD = 25V

27
–5.0
2.5
165
1

4

25
2.5
750
68

VOUT Quiescent Current – Burst Mode
Operation (Sleeping)Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3130/LTC3130-1 is tested under pulsed load conditions
such that TJ ≈ TA. The LTC3130E/LTC3130E-1 is guaranteed to meet
specifications from 0°C to 85°C junction temperature. Specifications overthe –40°C to 125°C operating junction temperature range are assured bydesign, characterization and correlation with statistical process controls.
The LTC3130I/LTC3130I-1 is guaranteed over the –40°C to 125°C
operating junction temperature range. The junction temperature (TJ) is
calculated from the ambient temperature (TA) and power dissipation (PD)according to the formula:
TJ = TA + (PD • θJA°C/W),
where θJA is the package thermal impedance. Note that the maximum
ambient temperature consistent with these specifications is determined by
specific operating conditions in conjunction with board layout, the rated
thermal package thermal resistance and other environmental factors.

100
34
2.40
135
3.15

UNITS
ms
V
V
mV
mA
V
mV
V
mV
V
µA

400
32
600

27
(VOUT–1)–7.0

MAX(VOUT)
17(VOUT)
17
–3.0
250
50

µA
%
%
mV
nA

Note 3: Specification is guaranteed by design and not 100% tested in
production.
Note 4: Current measurements are made when the output is not switching.
Note 5: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 165°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may result in device degradation or failure.
Note 6: Failure to solder the exposed backside of the package to the PC
board ground plane will result in a much higher thermal resistance.
Note 7: Switching time measurements are made in an open-loop test
configuration. Timing in the application may vary somewhat from these values due
to differences in the switch pin voltage during non-overlap durations when switch
pin voltage is influenced by the magnitude and duration of the inductor current.
Note 8: Voltage transients on the switch pin(s) beyond the DC limits
specified in the Absolute Maximum Ratings are non-disruptive to normal
operation when using good layout practices as described elsewhere in thedata sheet and application notes and as seen on the product demo board.
3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted.

70

Efficiency, VOUT = 3.3V,
PWM ModeOUT

80

60
50
40
30

70

50
40
30

60
50
40
30
20

10

10

10

0
0.01

0
0.01

1k

0.1

Efficiency, VOUT = 12V,
PWM ModeOUT

100

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

80
70

40
30

50
40

10
0
0.01

1k

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

30
20

1
10
100
LOAD CURRENT (mA)

0.1

3130 G04

1k

1
10
100
LOAD CURRENT (mA)

10
1
0.1

1k

0.001
0.01

Power Loss, VOUT = 3.3V, BurstMode
OUT Operation (LTC3130-1)
100

40
VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

30
20
10
0
0.01

0.1

1
10
100
LOAD CURRENT (mA)

10
1
0.1

3130 G07

0.001
0.01

1k

Efficiency, VOUT = 5V, Burst Mode
Operation(LTC3130-1)
OUT

80

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

0.01

1k

1
10
100
LOAD CURRENT (mA)90

EFFICIENCY (%)

POWER LOSS (mW)

50

0.1

3130 G06

100

60

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

0.01

90
80

1k

Power Loss, VOUT = 1.8V, BurstMode
OUT Operation (LTC3130-1)

3130 G05

Efficiency, VOUT = 3.3V, BurstMode
OUT Operation (LTC3130-1)

70

1
10
100
LOAD CURRENT (mA)

100

60

10

100

1k

70

20

0.1

Efficiency, VOUT = 1.8V, BurstMode
OUT Operation (LTC3130-1)

80

50

0.1

3130 G03

90

60

0
0.01

0
0.01

1k

POWER LOSS (mW)

90

1
10
100
LOAD CURRENT (mA)

3130 G02

EFFICIENCY (%)

100

EFFICIENCY (%)

70

20

1
10
100
LOAD CURRENT (mA)

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

80

20

0.1

Efficiency, VOUT = 5V,
vs Load,VOUT = 5V, PWM Mode
PWM
Mode

90

60

3130 G01

EFFICIENCY (%)

100

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

90

EFFICIENCY (%)

80
EFFICIENCY (%)

100

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

90

EFFICIENCY (%)

100

Efficiency, VOUT = 1.8V,
vs Load,VOUT = 1.8V, PWM Mode
PWM
Mode

0.1

1
10
100
LOAD CURRENT (mA)

70
60
50
40
VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

30
20
10

1k
3130 G08

0
0.01

0.1

1
10
100
LOAD CURRENT (mA)

1k3130 G09

3130f

For more information www.linear.com/LTC3130

5

LTC3130/LTC3130-1
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted.
1kPower Loss, VOUT = 5V, Burst
Mode(LTC3130-1)
VOUT =Operation
5V, Burst Mode100

Efficiency, VOUT = 12V, BurstMode
OUT Operation (LTC3130-1)

1kPower Loss, VOUT = 12V, BurstMode
OUT Operation (LTC3130-1)

90
80

1
0.1

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

0.01
0.001
0.01

0.1

1
10
100
LOAD CURRENT (mA)

70
60
50
40
VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

30
20
10
0
0.01

1k

0.1

1
10
100
LOAD CURRENT (mA)

Efficiency, VOUT = 8V,
PWM
OUT Mode (LTC3130)

80
70

50
40
30

1k

50
40

20
10
1
10
100
LOAD CURRENT (mA)

0
0.01

1k

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

30

1k

Power Loss , VOUT = 8V, Burst
Mode(LTC3130)
VOUT =Operation
8V, Burst Mode

0.1

1
10
100
LOAD CURRENT (mA)

101
VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

0.1

0.01
0.01

1k

0.1

1
10
100
LOAD CURRENT (mA)

Efficiency, VOUT = 15V
V(LTC3130)
OUT = 15V
1k

1k3130 G153130 G14

Power Loss, VOUT = 15V, BurstMode
OUT Operation (LTC3130)

100

90

Efficiency, VOUT = 24V(LTC3130)
OUT

90

80

80

60
50
40
30

EFFICIENCY (%)

100

70

POWER LOSS (mW)EFFICIENCY (%)

1
10
100
LOAD CURRENT (mA)

100

3130 G13

10

1

20

VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

10
0
0.01

6

0.1

3130 G12

Efficiency, VOUT = 8V, Burst Mode
Operation
VOUT = 8V, (LTC3130)
Burst Mode

60

10

100

0.01
0.01

1k

70

20

0.1

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

0.1

80

60

0
0.01

1

90

EFFICIENCY (%)

EFFICIENCY (%)

100

VIN = 2.5V
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V90

103130 G113130 G10100

POWER LOSS (mW)EFFICIENCY (%)

10

100

POWER LOSS (mW)

POWER LOSS (mW)

100

0.1

1
10
100
LOAD CURRENT (mA)

Burst Mode OPERATION:
VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

PWM:

1k3130 G16

0.1
0.01

0.1

1
10
100
LOAD CURRENT (mA)

60
50
40
30
20
10

1k
3130 G17

VIN = 3.6V
VIN = 5V
VIN = 12V
VIN = 24V

70

0
0.01

0.1

1
10
100
LOAD CURRENT (mA)

Burst Mode OPERATION:
VIN = 5V
VIN = 12V
VIN = 24V

PWM:

1k3130 G18

VIN = 5V
VIN = 12V
VIN = 24V
3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted.
Power Loss, VOUT = 24V, Burst Mode
Operation (LTC3130)
1k

VIN Shutdown Current vs
VIN (RUN = 0V, EXTVCC = 0V)

Maximum Output Current
vs VIN and VOUT

VOUT = 24V, Burst Mode

IN

700

OUT

0.90

600

0.80

10

400
300
VOUT = 1.8V
VOUT = 3.3V
VOUT = 5V
VOUT = 12V
VOUT = 25V

200

1

0.1
0.01

VIN = 5V
VIN = 12V
VIN = 24V
0.1

100

1
10
100
LOAD CURRENT (mA)

0

1k

0

5

10
15
VIN (V)

VIN UVLO Current
vs VIN (0.85V ≤ RUN ≤ 1.01V,
EXTVCC = 0V)
CC

0.30

0.10
0

25

1.00
0.80

0.40

10

15

20

25
3130 G21

No-Load Input Current in Burst
Mode Operation vs VIN and VOUT
(LTC3130-1,
MODE = 0V)
and V(LTC3130-1, MODE = 0V)

15

OUT

5.0

VOUT = 1.8V
VOUT = 3.3V
VOUT = 5V
VOUT =1 2V

4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0

5

0.20

5

3130 G20

10

0.60

0

VIN (V)IIN (μA)

20
IIN (μA)

0.5
0

5

10
15
VIN (V)

20

0

25

IN

10
15
VIN (V)20

253130 G25053130 G23

1015
VIN (V)20

253130 G24

Average Inductor Current Limit
vs
MPPC Voltage
vs MPPC Voltage
0.80
0.70

0.09

0.06
VOUT = 1.8V
VOUT = 3.3V
VOUT = 5V
VOUT = 12V
VOUT = 25V

0.03

5

5

0

25

OUT

10

0

20

0.12

IOUT (A)

15

IN

0.15

VOUT = 1.8V
VOUT = 3.3V
VOUT = 5V
VOUT = 12V
VOUT = 25V

20

10
15
VIN (V)

Burst Mode Operation, Load
Current Threshold vs VIN and
VOUT (MODE = 0V)

OUT

25

5

3130 G22

No-Load Input Current in Fixed
Frequency vs VIN and VOUT
(MODE = VCC)
30

0

INDUCTOR CURRENT LIMIT (A)VIN CURRENT (μA)

0.40

IOUT = 2μA (FB DIVIDER)
VOUT = 1.8V
VOUT = 3.3V
VOUT = 5V
VOUT = 12V
VOUT = 25V

25

1.20

IIN (mA)

0.50

OUT

30

1.40

0

0.60

No-Load Input Current in Burst
Mode Operation vs VIN and VOUT
(LTC3130, MODE = 0V)

1.60

0

0.70

0.20

20

3130 G19

1.80

VIN CURRENT (μA)

500
IOUT (mA)

POWER LOSS (mW)

100

CC

1.00

0

0

5

10
15
VIN (V)

20

0.60
0.50
0.40
0.30
0.20
0.10

25
3130 G26

0
0.95

0.98

1.01
1.04
MPPC (V)

1.07

1.10
3130 G27

3130f

For more information www.linear.com/LTC3130

7

LTC3130/LTC3130-1
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted.
Average Current Limit vsTemperature (Normalized to 25°C)

FB Voltage vs Temperature
LTC3130 (Normalized to 25°C)

LTC3130 (Normalized to 25 C)

LTC3130–1 (Normalized to 25 C)

0.00

0.00

–1.00

–0.10

–0.10

–2.00

–0.20

–3.00
–4.00
–5.00
–6.00
–7.00
–8.00

CHANGE IN OUTPUT VOLTAGE (%)

0

CHANGE IN FB VOLTAGE (%)

CHANGE IN AVERAGE CURRENT LIMIT (%)(Normalized to 25 C)

–0.30
–0.40
–0.50
–0.60
–0.70
–0.80

–9.00

–0.90

–10.00–50 –25–1.00–50 –250

25 50 75 100 125 150
TEMPERATURE (° C)

0

–4.00
–5.00
–6.00
–7.00
–8.00
–9.00
–10.00–50 –25

0

–0.90
–1.00
–50 –250

25 50 75 100 125 150
TEMPERATURE (° C)3130 G30

Accurate RUN Threshold vs
Temperature (Normalized to 25°C)

99

98

97
2.4

SwitchTemperature
DS(ON)vsvsTemperature
Switch R
Rdson

2.8

3.2
VCC (V)

3.6

4.0

–0.20
–0.30
–0.40
–0.50
–0.60
–0.70
–0.80
–0.90
–1.00
–50 –253130 G32

0.50

SW2(5V/DIV)

0.42

0.45
RDSON (Ω)

25 50 75 100 125 150
TEMPERATURE (° C)

Fixed Frequency PWM
Waveforms (Buck Region)

CC

0.45

0

3130 G33

SwitchvsVVCC
DS(ON)vsSwitch R
Rdson

0.55

RDSON (Ω)

–0.80

0.00

3130 G31

0.35

–0.70

–0.10

25 50 75 100 125 150
TEMPERATURE (° C)

0.40

–0.60

CHANGE IN RUN THRESHOLD (%)

–3.00

–0.50

CC

100

NORMALIZED OSCILLATOR FREQUENCY (%)

–2.00

–0.40

Oscillator Frequency vs VCC(Normalized
to VCC = 4V)
Oscillator Frequency
vs V(Normalized to 25 C)

–1.00

–0.30

3130 G29

Oscillator Frequency vsTemperature (Normalized to 25°C)
0

–0.20

25 50 75 100 125 150
TEMPERATURE (° C)3130 G28

CHANGE IN OSCILLATOR FREQUENCY (%)

Output Voltage vs Temperature
LTC3130–1 (Normalized to 25°C)

SW1(10V/DIV)

0.39

INDUCTORCURRENT(0.5A/DIV)

0.36

0.30

0.20
–50 –250

25 50 75 100 125 150
TEMPERATURE (° C)3131 G34

8200nsec/DIV

0.33

0.25

0.30
2.5

3

3.5
VCC (V)3130 G36

43134 G35

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted.
Fixed Frequency PWM
Waveforms (Buck-Boost Region)

Fixed Frequency PWM
Waveforms (Boost Region)

SW2(5V/DIV)

SW2(10V/DIV)SW1(5V/DIV)

SW1(5V/DIV)INDUCTORCURRENT(0.5A/DIV)INDUCTORCURRENT(0.5A/DIV)
200nsec/DIV

Fixed Frequency Output
Voltage Ripple
VOUT(50mV/DIV)INDUCTORCURRENT(0.2A/DIV)
03130 G37

3130 G38

200nsec/DIV

PWM to Burst Mode Operation
Transition

Burst Mode Operation Waveforms

VIN(10V/DIV)VCC(2V/DIV)

MODE PIN(2V/DIV)

VOUT(2V/DIV)INDUCTORCURRENT(0.2A/DIV)INDUCTORCURRENT(0.2A/DIV)INDUCTORCURRENT(0.2A/DIV)
20μsec/DIV

3130 G40

1msec/DIV3130 G41

2msec/DIV

5VOUT
ILOAD =10mA
COUT = 22µF

12VIN, 5VOUT,
ILOAD = 20mA, COUT = 22µF

COUT = 22µF

Start-Up Sequence When Raising
RUN Pin (VIN = 12V)

VCC Response to a Step on
EXTVCC (VIN > 4V)

VCC Response to a Step on
EXTVCC (VIN = 3V)

RUN(5V/DIV)

VCC(2V/DIV)

VCC(2V/DIV)

00

INDUCTORCURRENT(0.2A/DIV)EXTVCC(5V/DIV)
0

EXTVCC2msec/DIV3130 G42

VCC(2V/DIV)

VOUT(2V/DIV)

3138 G43

3130 G39

Start-Up Sequence When
Applying VIN (RUN Tied to VIN)

VOUT
(100mV/
DIV)

VOUT(50mV/DIV)

500nsec/DIV
12VIN, 5VOUT,
ILOAD = 0.5A, COUT = 22µF

(5V/DIV)01msec/DIV3130 G44

1msec/DIV3130 G45

3130f

For more information www.linear.com/LTC3130

9

LTC3130/LTC3130-1
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted.
Step Load Transient Response in
Fixed Frequency

VOUT(2V/DIV)
PGOOD(2V/DIV)

VOUT(100mV/DIV)

VOUT(100mV/DIV)INDUCTORCURRENT(0.2A/DIV)INDUCTORCURRENT(0.5A/DIV)3130 G46

500μsec/DIV
12VIN, 5VOUT,
50mA to 500mA LOAD STEP
COUT = 22µF, L = 10μH

PGOOD Response to a Drop in
VOUT Due to a Step Overload

Step Load Transient Response in
Burst Mode Operation

INDUCTORCURRENT(0.5A/DIV)
500μsec/DIV

3130 G47

1msec/DIV
12VIN, 5VOUT,
10mA to 250mA LOAD STEP
COUT = 22µF, L = 10μH

MPPC Response to an Overload(VMPPC Set to 5V at VIN)

3130 G48

VIN Line Step Response in
Fixed Frequency

VOUT(5V/DIV)
VIN(5V/DIV)

VOUT(1V/DIV)

VIN(10V/DIV)INDUCTORCURRENT(0.2A/DIV)INDUCTORCURRENT(0.2A/DIV)3130 G49

2msec/DIVVOC = 9V
VOUT = 12V
RIN = 20Ω
CIN = 33μF

VOUT
(2V/DIV)

VOUT(1V/DIV)

VIN(10V/DIV)INDUCTORCURRENT(0.2A/DIV)
50μsec/DIV

3130 G51

5VOUT,
5V TO 25V VIN STEP,
COUT = 22µF, L = 10μH,
LIGHT LOAD

103130 G50

Output Voltage Short-Circuit
Waveforms

VIN Line Step Response in
Burst Mode Operation

INDUCTORCURRENT(0.2A/DIV)

50μsec/DIV
5VOUT,
5V TO 25V VIN STEP,
COUT = 22µF, L = 10μH,
LIGHT LOAD

10μsec/DIV

3130 G52

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
PIN FUNCTIONS (QFN/MSOP)
BST1 (Pin 1/Pin 2): Boot-Strapped Floating Supply forHigh Side NMOS Gate Drive. Connect to SW1 through a
22nF capacitor, as close to the part as possible.
PVIN (Pin 2/Pin 4): Power Input for the Buck-Boost
Converter. A 4.7μF or larger bypass capacitor should beconnected between this pin and the ground plane. The
capacitor should be located as close to the IC as possible.
When powered through long leads or from a high ESR
source, a larger bulk input capacitor (typically 47μF orlarger) may be required.
VIN (Pin 3/Pin 5): Input Voltage for the VCC Regulator.
Connect a minimum of 1µF ceramic decoupling capacitor
from this pin to the ground plane.
RUN (Pin 4/Pin 6): Input to the Run Comparator. Raising this pin above 1.05V enables the converter. Pull thispin above 0.6V (typical) to put the converter in “standby
mode”, where the internal reference will be enabled, but
the part will not be switching. Connecting this pin to a
resistor divider from VIN to ground allows programmingan accurate VIN start threshold. To enable the converter
all the time, tie RUN to VIN. See the Operation section ofthis data sheet for more guidance.
VCC (Pin 5/Pin 7): Output Voltage of the Internal 4V
Voltage Regulator. This is the supply pin for the internal
circuitry. Bypass this output with a minimum of 4.7µF
ceramic capacitor. This internal regulator is powered by
VIN or EXTVCC. Note that VCC should not be back-driven.
VCC can be used to power external circuitry as long as
the peak load current doesn’t exceed 2mA. Note that thisadded load will increase the minimum required operating
VIN voltage by up to 60mV.
NC (Pin 17, QFN Only): Unused. This pin should begrounded.
MPPC (Pin 6/Pin 8): Maximum Power Point Control
Programming Input. Connect this pin to a resistor divider
from VIN to ground to enable MPPC functionality. If thedivider voltage drops below 1.0V (typical), the inductor
current will be reduced to servo VIN to the programmed
minimum voltage, as set by the divider. Note that this pin
is very noise sensitive, therefore minimize trace length andstray capacitance. Refer to the Applications Information
section of this data sheet for more detail on programming
the MPPC. If this function is not needed, tie the pin to VCC.
GND (Pins 7-8, Exposed Pad Pin 21/Pin 1, Exposed Pad
Pin 17): Ground. Provide a short direct PCB path between
GND and the ground plane that the exposed pad is soldered
to. The exposed pad must be soldered to the PCB groundplane. It serves as a power ground connection, and as ameans of conducting heat away from the die.
FB (Pin 9/Pin 9 (LTC3130)): Feedback input to the error
amplifier. Connect to a resistor divider from VOUT to ground.
The output voltage can be adjusted from 1.0V to 25V by:
 R1
VOUT = 1.00V •  1+  R2 

(Re fer to Figure 2)

Note that this pin is very noise sensitive, therefore minimize
trace length and stray capacitance. Please refer to theApplications Information section of this data sheet for moredetail on setting the FB voltage divider, and the optionaluse of an optional feed-forward capacitor.
VS2 (Pin 9/Pin 9 (LTC3130-1)): Output Voltage Select Pin.
Connect this pin to ground or VCC to program the output
voltage (see Table 1). This pin can also be dynamically driven
by any logic signal that satisfies the specified thresholds.
ILIM (Pin 10/Pin 10 (LTC3130)): Programming pin to
select between 250mA or 660mA average minimum inductor current limit. Please see the Maximum Output Current
curve in the Typical Performance Characteristics section.
ILIM = Low (ground): Sets the average inductor current
limit to 250mA (minimum) for low current applications
ILIM = High (tie to VCC): Sets the average inductor
current limit to 660mA (minimum)
This pin can also be dynamically driven by any logic signalthat satisfies the specified thresholds.

3130f

For more information www.linear.com/LTC3130

11

LTC3130/LTC3130-1
PIN FUNCTIONS (QFN/MSOP)
VS1 (Pin 10/Pin 10 (LTC3130-1)): Output Voltage SelectPin. Connect this pin to ground or VCC to program theoutput voltage (see Table 1). This pin can also be dynamically driven by any logic signal that satisfies the specified
thresholds.
Table 1. VOUT Program Settings for the LTC3130-1
VS2

VS1

VOUT

0

0

1.8V

0

VCC

3.3V

VCC

0

5.0V

VCC

VCC

12V

MODE (Pin 11/Pin 11): Mode Select Pin.
MODE = Low (ground): Enables automatic Burst Modeoperation
MODE = High (tie to VCC): Fixed frequency PWM
operation
This pin can also be dynamically driven by any logic signalthat satisfies the specified thresholds. There is an internal
3MΩ pull-down resistor connected to MODE once switching is enabled, to prevent it from floating.
EXTVCC (Pin 12/Pin 12): Second Input to the Internal
VCC Regulator. This pin can be tied to VOUT or anothervoltage between 3V and 25V. If this input is used, it will
power the IC, reducing the quiescent current draw on
VIN in buck applications and allowing the converter tooperate from a VIN voltage down to 1V or less. A 4.7µF
decoupling capacitor is recommended on this pin unless
it is tied directly to the VOUT decoupling capacitor. If notused, this pin should be grounded.

12

PGOOD (Pin 13/Pin 13): Open-drain output that pulls toground when FB (LTC3130) or VOUT (LTC3130-1) drops
too far below its regulated voltage. Connect a pull-up
resistor from this pin to a positive supply. Note that if a
supply voltage is present on VIN or EXTVCC, this pin will
be forced low in shutdown or UVLO.
VOUT (Pin 14/Pin 14): Output Voltage of the Converter.
Connect a minimum value of 4.7µF ceramic capacitor
from this pin to the ground plane. See the Applications
Information section of this data sheet for guidance.
BST2 (Pin 16/Pin 15): Boot-Strapped Floating Supply forHigh Side NMOS Gate Drive. Connect to SW2 through a
22nF capacitor, as close to the part as possible.
SW2 (Pin 15/Pin 16): Switch Pin. Connect to the otherside of the inductor. Keep PCB trace lengths as short andwide as possible to reduce EMI and parasitic resistance.
PGND (Pins 18-19)/(Pin 1): Power Ground. Provide a short
direct PCB path between PGND and the ground plane.
SW1 (Pin 20/Pin 3): Switch Pin. Connect to one side of
the inductor. Keep PCB trace lengths as short and wide as
possible to reduce EMI and parasitic resistance.

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
LTC3130 BLOCK DIAGRAM
PVIN

EXTVCC

VIN

BST

SW1

SW2

BST2

VREF

VCC_GD

LDO

VCC

1.05V

1.0V
VREF_GD

B

DRIVERVSENSEC

DRIVERSTART+–

VSENSE

+
–

1.2A

ON

+
–

IPK

UV

LOGIC

FB
0.7V
VSENSEENABLEVSENSE
50mA

MPPC
MODE

DRIVER

D

+
–

1.0V

RESET

IZERO

THERMAL
SHUTDOWN+–

SOFT-START

3M
VCC_GD

+
–

100mV

–
+

+
–

0.6V

A

VC

+
–

RUN

DRIVERVOUTISENSE

4V
VREF

VOUT
VCC

VCC

+
–

VIN

1.0V

OSC

–
+

600mA
SLEEP

GND

200mA

PGND

CLAMP

–7.5%

–
+

PGOOD

ILIM
3130 BD

VCC

3130f

For more information www.linear.com/LTC3130

13

LTC3130/LTC3130-1
LTC3130-1 BLOCK DIAGRAM
PVIN

EXTVCC

VIN

BST

SW1

SW2

BST2

VCC
1.0V

VCC_GD

LDO

VCC

1.05V

DRIVERB

VSENSEC

VS2DRIVER

VOUT
SELECTINPUTSSTART+–VSENSE

+
–

1.2A

ON

+
–

IPK

UV

LOGIC

0.7V
VSENSEENABLEVSENSE
50mA

MPPC
MODE

VS1

DRIVER

+
–

1.0V

RESET

IZERO

THERMAL
SHUTDOWN

100mV

–
+

+
–

PWM

SOFT-START

3M
VCC_GD

+
–

+
–

0.6V

D

VC

+
–

RUN

A
ISENSE

1.0V
VREF_GD

VOUT

VCC
DRIVER

4V
VREF

VOUT

+
–

VIN

FB
1.0V

OSC

600mA

SLEEP

GND

–
+
CLAMP

–7.5%

–
+

PGOOD

PGND
31301 BD

14

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
OPERATION
INTRODUCTION
The LTC3130/LTC3130-1 are 1.6µA quiescent current,monolithic, current mode, buck-boost DC/DC convertersthat can operate over a wide input voltage range of 0.6V
(2.4V to start) to 25V and provide up to 600mA to theload. The LTC3130 has a FB pin for programming VOUT
anywhere from 1V to 25V, while the LTC3130-1 features
four fixed, user-selectable output voltages which can beselected using the two digital programming pins. Internal,
low RDS(ON) N-channel power switches reduce solution
complexity and maximize efficiency. A proprietary switch
control algorithm allows the buck-boost converter tomaintain output voltage regulation with input voltages thatare above, below or equal to the output voltage. Transitions between the step-up or step-down operating modes
are seamless and free of transients and sub-harmonic
switching, making this product ideal for noise sensitive
applications. The LTC3130/LTC3130-1 operate at a fixednominal switching frequency of 1.2MHz, which provides
an ideal trade-off between small solution size and highefficiency. Current mode control provides inherent input
line voltage rejection, simplified compensation and rapid
response to load transients.
Burst Mode capability is included in the LTC3130/
LTC3130‑1 and is user-selected via the MODE pin. In
Burst Mode operation, exceptional light-load efficiency isachieved by operating the converter only when necessary
to maintain voltage regulation. The Burst Mode quiescentcurrent is a miserly 1.6µA. When Burst Mode operationis selected, the converter automatically switches to fixed
frequency PWM mode at higher loads. (Please refer to the
Typical Performance Characteristic curves for the modetransition point at different input and output voltages.)
If the application requires extremely low noise under all
load conditions, continuous PWM operation can also be
selected via the MODE pin by pulling it high.
A MPPC (maximum power point control) function is also
provided that prevents the converter from pulling enoughcurrent to drop VIN below a user-programmed thresholdunder load. This servos the input voltage of the converter
to a programmable point for maximum power extraction
when operating from various non-ideal power sources
such as photovoltaic cells.

The LTC3130/LTC3130-1 also feature an accurate RUN
comparator threshold with hysteresis, allowing thebuck/boost DC/DC converter to turn on and off at userprogrammed VIN voltage thresholds. With a wide voltage
range, 1.6µA Burst Mode current and programmable
RUN and MPPC pins, these highly integrated monolithic
converters are well suited for many diverse applications.
PWM MODE OPERATION
If the MODE pin is high (or if the load current on the converter is high enough to command PWM mode operation
with MODE low), the LTC3130/LTC3130-1 operate in a
fixed 1.2MHz PWM mode using an internally compensatedaverage current mode control loop. PWM mode minimizes
output voltage ripple and yields a low noise switchingfrequency spectrum. A proprietary switching algorithm
provides seamless transitions between operating modes
and eliminates discontinuities in the average inductor
current, inductor ripple current and loop transfer function
throughout all modes of operation. These advantages
result in increased efficiency, improved loop stability andlower output voltage ripple in comparison to the traditional
buck-boost converter.
Figure 1 shows the topology of the power stage which iscomprised of four N-channel DMOS switches and theirassociated gate drivers. In PWM mode operation bothswitch pins transition on every cycle independent of the
input and output voltages. In response to the internal
control loop command, an internal pulse width modulator
generates the appropriate switch duty cycle to maintainregulation of the output voltage.
CBST1

BST1

CBST2

L

PVIN

SW1

SW2 VOUT

BST2
VCC

VCC
A

D

VCC

VCC
B
PGND

C
PGND

Figure 1. Power Stage Schematic

LTC31303130 F01

3130f

For more information www.linear.com/LTC3130

15

LTC3130/LTC3130-1
OPERATION
When stepping down from a high input voltage to a lower
output voltage, the converter operates in buck mode andswitch D remains on for the entire switching cycle except
for the minimum switch low duration (typically 70ns). During the switch low duration, switch C is turned on which
forces SW2 low and charges the flying capacitor, CBST2.
This ensures that the switch D gate driver power supply
rail on BST2 is maintained. The duty cycle of switches A
and B are adjusted to maintain output voltage regulationin buck mode.
If the input voltage is lower than the output voltage, theconverter operates in boost mode. Switch A remains on
for the entire switching cycle except for the minimum
switch low duration (typically 70ns). During the switch
low duration, switch B is turned on which forces SW1
low and charges the flying capacitor, CBST1. This ensuresthat the switch A gate driver power supply rail on BST1 ismaintained. The duty cycle of switches C and D are adjusted
to maintain output voltage regulation in boost mode.
Oscillator
The LTC3130/LTC3130-1 operate from an internal oscillator with a nominal fixed frequency of 1.2MHz. This allows
the DC/DC converter efficiency to be maximized while stillusing small external components.
Current Mode Control
The LTC3130/LTC3130-1 utilizes average current mode
control for the pulse width modulator. Current mode
control, both average and the better known peak method,
enjoy some benefits compared to other control methods
including: simplified loop compensation, rapid response
to load transients and inherent line voltage rejection.
Referring to the Block Diagrams, a high gain, internallycompensated transconductance voltage error amplifiermonitors VOUT through a voltage divider connected to the
FB pin (LTC3130) or via the internal VOUT voltage divider(LTC3130-1). The error amplifier output is used by thecurrent mode control loop to command the appropriate
inductor current level. The inverting input of the internallycompensated average current amplifier is connected tothe inductor current sense circuit. The average current
amplifier’s output is compared to the oscillator ramps,

16

and the comparator outputs are used to control the duty
cycle of the switch pins on a cycle-by-cycle basis.
The voltage error amplifier makes adjustments to the current command as necessary to maintain VOUT in regulation.
The voltage error amplifier therefore controls the outer
voltage regulation loop. The average current amplifier
makes adjustments to the inductor current as directedby the voltage error amplifier, and is commonly referred
to as the inner current loop amplifier.
The average current mode control technique is similar topeak current mode control except that the average current
amplifier, by virtue of its configuration as an integrator,
controls average current instead of the peak current. Thisdifference eliminates the peak to average current error
inherent to peak current mode control, while maintaining
most of the advantages inherent to peak current mode
control.
The compensation components required to ensure proper
operation have been carefully selected and are integrated
within the LTC3130/LTC3130-1.
Inductor Current Sense and Maximum Average
Output Current
As part of the current control loop required for current
mode control, the LTC3130/LTC3130-1 include a pairof current sensing circuits that measure the buck-boost
converter inductor current.
The voltage error amplifier output (VC) is internally clamped
to an accurate threshold. Since the average inductor current
is proportional to VC, the clamp level sets the maximum
average inductor current that can be programmed by the
inner current loop. Taking into account the current sense
amplifier’s gain, the maximum average inductor current is approximately 850mA typical (660mA minimum,
assuming the ILIM pin is pulled high for the LTC3130).
In buck mode, the output current is approximately equal
to 90% of the inductor current IL (due to the forced low
time of the B and C switches, where no current is delivered
to the output):
IOUT(BUCK) ≈ 0.9 • IL

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
OPERATION
In boost mode, the output current is related to average
inductor current and duty cycle by: V 
IOUT(BOOST) ≈ IL •  IN  • η VOUT 

Since the output current in boost mode is reduced by the
step-up ratio of VIN/VOUT, the output current rating in buckmode is always greater than in boost mode. Also, because
boost mode operation requires a higher inductor current
for a given output current compared to buck mode, theefficiency (η) in boost mode will generally be lower due
to higher IL2 • RDS(ON) losses in the power switches. This
will further reduce the output current capability in boost
mode. In either operating mode, however, the inductor
peak-to-peak ripple current does not play a major rolein determining the output current capability, unlike peakcurrent mode control.
The LTC3130/LTC3130-1 measure and control average
inductor current, and therefore, the inductor ripple current magnitude has little effect on the maximum current
capability (in contrast to an equivalent peak current mode
converter). Under most conditions in buck mode, theLTC3130/LTC3130-1 are capable of providing a minimumof 600mA to the load. Refer to the Typical Performance
Characteristics section for more details. In boost mode,as described previously, the output current capability isrelated to the boost ratio. For example, for a 5V VIN to 15V
output application, the LTC3130/LTC3130-1 can provide
up to 150mA typical to the load. Refer to the Typical
Performance Characteristics section for more detail on
output current capability.
Programming VOUT (LTC3130)
The output voltage of the LTC3130 is programmed using
an external resistor divider from VOUT to ground with thedivider tap connected to the FB pin, as shown in Figure 2,
according to the equation:
 R1
VOUT = 1.00V •  1+  R2 

(Re fer to Figure 2)

The output voltage can be set anywhere from 1.0V to 25V.
An optional feed-forward capacitor can be added in parallelwith R1 (as shown in Figure 2) to reduce Burst Mode ripple
and improve transient response of the voltage loop. The
typical feed-forward capacitor value can be calculated by:
CFF (pF ) =40
R1 (Meg)

In some applications, where the voltage-loop bandwidthis high, it may prove beneficial to add a resistor in series
with the feed-forward capacitor to limit the high frequency gain. The value isn’t critical, and resistor values of
VOUT
COUT

LTC3130

R1

CFF OPTIONAL
FEED-FORWARD

RFF
FB
R2
GND
3130 F02

Figure 2. VOUT Feedback Divider (Showing Optional
Feed-Forward Capacitor)

approximately R1/20 are generally recommended.
VOUT Programming Pins (LTC3130-1)
The LTC3130-1 has a precision internal voltage divider
on VOUT, eliminating the need for high value external
feedback resistors. This not only eliminates two external
components, it minimizes no-load quiescent current
by using very high resistance values that would not bepractical when used externally due to the effects of noiseand board leakages that would cause VOUT regulation errors. The tap point on this divider is digitally selected byusing the VS1 and VS2 pins to program one of four fixed
output voltages.
The VS1 and VS2 pins can be grounded or connected
to VCC to select the desired output voltage, according toTable 1. They can also be driven dynamically from external
logic signals, as long as the pin’s specified logic levels are
satisfied and the absolute maximum ratings for the pins
are not exceeded.
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17

LTC3130/LTC3130-1
OPERATION
Note that driving VS1 or VS2 to a logic high that is below
the VCC voltage can result in an increase of up to 1µA of
current draw from VCC per VS pin. This does not occur in
shutdown or if VCC is below its UVLO threshold, in whichcase these inputs are disabled and will not cause any extra
current draw.
Table 1. VOUT Program Settings for the LTC3130-1
VS2

VS1

VOUT

0

0

1.8V

0

VCC

3.3V

VCC

0

5.0V

VCC

VCC

12V

Programming the ILIM Threshold (LTC3130 only)
The LTC3130 has two average current limit settings,
which are set by the ILIM pin. If ILIM is pulled high (tiedto VCC), the average inductor current limit will be set to
660mA (minimum). If the ILIM pin is pulled low (tied to
ground), the average inductor current limit will be reduced
to 250mA (minimum). This setting can be used in low
power applications to reduce the maximum current draw
from sources that may suffer excessive voltage drop at
the full 600mA current limit setting, or to simply reducethe maximum output current.
VOUT Undervoltage and Foldback Current Limit
The LTC3130/LTC3130-1 include a foldback current limit
feature to reduce power dissipation into a shorted output.
When VOUT is less than 0.7V (typical), the average current
limit is reduced to about half of its normal value. In thecase of the LTC3130 with the ILIM pin set low, the average
inductor current limit has already been cut in half and will
not be further reduced during undervoltage.
Overload Peak Current Limit
The LTC3130/LTC3130-1 also have peak overload current(IPEAK) and zero current (IZERO) comparators. The IPEAK
current comparator turns off switch A for the remainderof the switching cycle if the inductor current exceeds the
maximum threshold of 1.3A (typical). An inductor current

18level of this magnitude may occur during a fault, such as
an output short circuit, or possibly for a few cycles during large load or input voltage transients. Note that it may
also occur if there is excessive inductor ripple current (orinductor saturation) due to an improperly sized inductor.
Note that if a peak current limit is reached while VOUT is
also less than 0.7V typical (which would be indicative ofa shorted output), a soft-start cycle will be triggered.
IZERO Comparator
The LTC3130/LTC3130-1 feature near discontinuous
inductor current operation at light output loads by virtueof the IZERO comparator circuit. By limiting the reverse
current magnitude in PWM mode, a balance between low
noise operation and improved efficiency at light loads isachieved. The IZERO threshold is set near the zero current
level in PWM mode, and as a result the reverse current
magnitude will be a function of inductance value and output voltage due to the comparator’s propagation delay. In
general, higher output voltages and lower inductor values
will result in increased peak reverse current.
In automatic Burst Mode operation (MODE pin low), the
IZERO threshold is increased so that reverse inductor current does not normally occur. This maximizes efficiency
at light loads.
Note that reverse current is also inhibited during softstart (regardless of the MODE pin setting) to prevent VOUT
discharge when starting up into pre-biased outputs.
Burst Mode OPERATION
When the MODE pin is held low, the LTC3130/LTC3130-1
are configured for automatic Burst Mode operation. As aresult, the buck-boost DC/DC converter will operate withnormal continuous PWM switching above a predetermined
minimum output load and will automatically transition to
power saving Burst Mode operation below this output
load level. Refer to the Typical Performance Characteristics section of this data sheet to determine the Burst
Mode transition threshold for various combinations of
VIN and VOUT.

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LTC3130/LTC3130-1
OPERATION
If MODE is low, at light output loads, the LTC3130/
LTC3130‑1 go into a standby or sleep state when the
output voltage achieves its nominal regulation level. The
sleep state halts PWM switching and powers down all
non-essential functions of the IC, significantly reducing
the quiescent current of the converter to just 1.6µA typical.
This greatly improves overall power conversion efficiency
when the output load is light. Since the converter is notoperating in sleep, the output voltage will slowly decay at a
rate determined by the output load current and the output
capacitor value. When the output voltage has decayed by asmall amount, the LTC3130/LTC3130-1 wake and resume
normal PWM switching operation until the voltage on VOUT
is restored to the previous level. If the load is very light,
the converter may only need to switch for a few cycles torestore VOUT and may sleep for extended periods of time,
significantly improving efficiency. If the load is suddenly
increased above the burst transition threshold, the partwill automatically resume continuous PWM operation until
the load is once again reduced.
Note that Burst Mode operation is inhibited until soft-startis done, the MPPC pin is greater than 1.05V and VOUT hasreached 95% of regulation.
Soft-Start
The LTC3130/LTC3130-1 soft-start circuit minimizes input
current transients and output voltage overshoot on initial
power up. The required timing components for soft-start
are internal to the IC and produce a nominal average current limit soft-start duration of approximately 12ms. Theinternal soft-start circuit slowly ramps the error amplifier
output. In doing so, the maximum average inductor current
is also slowly increased, starting from zero. Soft-start isreset if the RUN pin drops below the accurate run threshold,
VCC drops below its UVLO threshold, a thermal shutdown
occurs, or a peak current limit occurs while VOUT is lessthan 0.7V typical.
Note that because the average current limit is being softstarted, the VOUT rise time will be load dependent, and istypically less that 12ms.

VCC Regulator and EXTVCC Input
An internal low dropout regulator (LDO) generates a nominal 4V VCC rail from VIN, or from EXTVCC if a valid EXTVCC
voltage is present. The VCC rail powers the internal control
circuitry and the gate drivers of the LTC3130/LTC3130-1.
The VCC regulator is enabled even in shutdown, but will
regulate to a lower voltage. The VCC regulator includes
current-limit protection to safeguard against accidental
short-circuiting of the VCC rail. VCC should be decoupledwith a 4.7µF ceramic capacitor located close to the IC.
During start-up, the IC will choose the higher of VIN or
EXTVCC to generate VCC. Once VCC is above its rising UVLO
threshold, EXTVCC will continue to be used if it is above
3.0V typical, otherwise VIN will be used. This allows startup from low VIN sources (in applications where a valid
EXTVCC voltage is present), while minimizing LDO power
dissipation after start-up in applications where VIN may
be much higher than VCC.
Use of the EXTVCC input allows the converter to operatefrom VIN voltages less than 1V, as long as EXTVCC is held
in its operating range of 3.0V minimum and 25V maximum.
If EXTVCC is tied to VOUT in buck applications, it will also
reduce the input current drawn from VIN, thereby increasing
converter efficiency, especially at light loads.
If an independent source, such as a battery or anothersupply rail, is used to power EXTVCC, then the IC can startup and operate at any input voltage, from 25V down to(theoretically) 0V (assuming the RUN pin is held above
1.05V). In practice, the minimum VIN voltage capability
will be application specific, determined by the required
output voltage and output current of the converter. Dueto the rapid drop in efficiency at very low input voltages,
the practical VIN limit is usually around 0.6V, assuming a
low resistance source, and that the step-up ratio to VOUT
doesn’t become duty cycle limited. Refer to the Typical
Performance Characteristic curves for the output voltage
and current capability versus VIN.
If not used, EXTVCC should be grounded.

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19

LTC3130/LTC3130-1
OPERATION
Undervoltage Lockout (UVLO)
The VCC UVLO has a falling voltage threshold of 2.175V(typical). If the VCC voltage falls below this threshold, IC
operation is disabled until VCC rises above 2.30V (typical).
Therefore, if a valid voltage source is not present on
EXTVCC, the minimum VIN for the part to start up is 2.30V(typical).
Note that until VCC is above the UVLO threshold, the partwill remain in a low quiescent current state (1.4µA typical).
This facilitates start-up from very weak sources.
RUN Pin Comparator
When RUN is driven above its logic threshold (0.6V typical), the internal voltage reference and the PGOOD circuit
are enabled (assuming VCC is above 2.30V typical). If thevoltage on RUN is increased further so that it exceeds
the RUN comparator’s accurate rising threshold (1.05V
typical), all functions of the buck-boost converter will beenabled and a start-up sequence will ensue. The RUN pin
comparator has 100mV of hysteresis, so operation will
be inhibited if the pin drops below 0.95V.
Therefore, with the addition of an optional resistor divider
as shown in Figure 3, the RUN pin can be used to establish user-programmable turn-on and turn-off (UVLO)
thresholds. This feature can be utilized to minimize battery
drain below a programmed input voltage, or to operate theconverter in a hiccup mode from very low current sources.
LTC3130
VIN
1.05V
R3

–
+

ACCURATE THRESHOLD
ENABLE SWITCHING

RUN
R4
0.6V

+
–

ENABLE VREF
AND PGOOD
LOGIC THRESHOLD
3130 F03

Figure 3. Accurate RUN Pin Comparator

20

If RUN is brought below the accurate comparator falling
threshold, the buck-boost converter will inhibit switching,but the VCC regulator and control circuitry will remain
powered. In this state, the typical VIN quiescent current isonly 1.4µA, in order to completely shut down the IC andreduce the VIN current to 500nA (typical), it is necessary
to ensure that RUN is brought below its minimum low
logic threshold of 0.2V.
RUN can be tied directly to VIN to continuously enable theIC when the input supply is present. Also note that RUN
can be driven above VIN or VOUT as long as it stays within
the absolute maximum rating of 25V.
The converter is enabled when the voltage on RUN exceeds
1.05V (nominal). Therefore, the turn-on voltage thresholdon VIN is given by: R3 
VIN(TURNON) = 1.05V •  1+ 
 R4 
Once the converter is enabled, the RUN comparator
includes a built-in hysteresis of 100mV, so that the turnoff threshold will be :
 R3 
VIN(TURNOFF) = 0.95V •  1+ 
 R4 
The RUN comparator is designed to be relatively noise
insensitive, but there may be cases due to PCB layout,
very large value resistors for R3 and R4, or proximity
to noisy components where noise pickup is unavoidable
and may cause the turn-on or turn-off of the IC to beintermittent. In these cases, a small filter capacitor canbe added across R4.
PGOOD Comparator
The LTC3130/LTC3130-1 provide an open-drain PGOOD
output that pulls low if FB (LTC3130) or VOUT (LTC3130‑1)
falls more than 7.5% (typical) below its programmed
value. When VOUT rises to within 5% (typical) of its
programmed value, the internal PGOOD pull-down willturn off and PGOOD will go high if an external pull-up
resistor has been provided. An internal filter prevents

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LTC3130/LTC3130-1
OPERATION
nuisance trips of PGOOD due to short transients on VOUT.
PGOOD can be pulled up to any voltage, as long as theabsolute maximum rating of 25V is not exceeded, andas long as the absolute maximum sink current rating of
12mA is not exceeded when PGOOD is low.

The MPPC divider resistor values can be in the MΩ range
so as to minimize the input current in very low power applications. However, stray capacitance and noise pickup
on the MPPC pin must also be minimized. If the MPPC
function is not required, the MPPC pin should be tied to VCC.

Note that PGOOD will be driven low if VCC is below its UVLO
threshold or if the part is in shutdown (RUN below its logic
threshold). PGOOD is not affected by the accurate RUN
threshold. Therefore, if PGOOD is pulled up to VIN or VCC,
this will add to the VIN quiescent current in shutdown and
UVLO, when PGOOD is low. For the lowest possible VIN
current in shutdown or UVLO, PGOOD should be pulled
up to VOUT or some other source.

Beware of adding a noise filter capacitor to the MPPC pin,as the added filter pole may cause the MPPC control loop
to be unstable.

Maximum Power Point Control (MPPC)
The MPPC input of the LTC3130/LTC3130-1 can be usedwith an optional external voltage divider to dynamicallyadjust the commanded inductor current in order to maintain a minimum input voltage when using high resistancesources, such as photovoltaic panels, so as to maximize
input power transfer and prevent VIN from dropping too
low under load.
Referring to Figure 4, the MPPC pin is internally connectedto the noninverting input of a gm amplifier, whose inverting input is connected to the 1.0V reference. If the voltage
at MPPC, using the external voltage divider, falls below
the reference voltage, the output of the amplifier pulls
the internal VC node low. This reduces the commanded
average inductor current so as to reduce the input current
and regulate VIN to the programmed minimum voltage,as given by:

Note that because Burst Mode operation will be inhibited
if the MPPC loop takes control, the converter will be operating in fixed frequency mode, and will therefore requirea minimum of about 6mA of continuous input current tooperate. For operation from weaker sources, such as small
indoor solar panels, refer to the Applications Information
section to see how the RUN pin may be programmed tocontrol the converter in a hysteretic manner while providing an effective MPPC function by maintaining VIN at thedesired voltage. This technique can be used with sources
as weak as 3µA (enough to power the IC in UVLO and theexternal RUN divider).
VIN
RS

CIN

R5

+
–

VSOURCE

MPPC

+
–

R6

VIN

LTC3130

1.0V

FB

+
–

VC
CURRENTCOMMANDVOLTAGEERROR AMP

3130 F04

 R5 
VIN(MPPC) = 1.00V •  1+ 
 R6 

Figure 4. MPPC Amplifier with External Resistor Divider

Note that external compensation should not be requiredfor MPPC loop stability if the input filter capacitor, CIN,
is at least 22µF.

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21

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
A standard application circuit for the LTC3130-1 is shownon the front page of this data sheet. There are numerous
other application examples for both the LTC3130-1 and
LTC3130 shown in the Typical Applications section ofthis data sheet.
The appropriate selection of external components is dependent upon the required performance of the IC in eachparticular application given considerations and trade-offs
such as PCB area, input and output voltage range, output
voltage ripple, transient response, required efficiency,
thermal considerations and cost. This section of the data
sheet provides some basic guidelines and considerations
to aid in the selection of external components and the design of the applications circuit, as well as more application
circuit examples.
VCC Capacitor Selection
The VCC output of the LTC3130/LTC3130-1 is generated
from VIN or EXTVCC by a low dropout linear regulator. The
VCC regulator has been designed for stable operation witha wide range of output capacitors. For most applications,a low ESR capacitor of at least 4.7µF should be used. The
capacitor should be located as close to the VCC pin as possible and connected to the VCC pin and ground through theshortest traces possible. VCC is the regulator output andis also the internal supply pin for the IC control circuitry
as well as the gate drivers and boost rail charging diodes.
Inductor Selection
The choice of inductor used in LTC3130/LTC3130-1
application circuits influences the maximum deliverable
output current, the converter bandwidth, the magnitudeof the inductor current ripple and the overall converter
efficiency. The inductor must have a low DC series resistance or output current capability and efficiency will becompromised. Larger inductor values reduce inductor
current ripple but do not increase output current capability
as is the case with peak current mode control. Larger value
inductors also tend to have a higher DC series resistance22

for a given case size, which will have a negative impact on
efficiency. Larger values of inductance will also lower theright half plane (RHP) zero frequency when operating inboost mode, which can compromise loop stability. Nearly
all LTC3130/LTC3130-1 application circuits deliver thebest performance with an inductor value between 3.3µH
and 15µH, depending on VIN and VOUT. Buck mode only
applications can use the larger inductor values as they
are unaffected by the RHP zero, while mostly boost applications generally require inductance on the low end of
this range depending on how large the step-up ratio is.
Regardless of inductor value, the saturation current rating
should be selected such that it is greater than the worst-caseaverage inductor current plus half of the ripple current. The
peak-to-peak inductor current ripple for each operationalmode can be calculated from the following formula, where
f is the switching frequency (1.2MHz), L is the inductancein µH and tLOW is the switch pin minimum low time inµs. The switch pin minimum low time is typically 0.07µs.
∆IL(P-P)(BUCK) =VOUT  VIN – VOUT   1
 – tLOW  Amps


L 
VIN
 f

∆IL(P-P)(BOOST) =VIN  VOUT – VIN   1
 – tLOW  Amps

L  VOUT  f

It should be noted that the worst-case peak-to-peak inductor ripple current occurs when the duty cycle in buckmode is minimum (highest VIN) and in boost mode when
the duty cycle is 50% (VOUT = 2 • VIN). As an example, if
VIN (minimum) = 2.5V and VIN (maximum) = 15V, VOUT
= 5V and L = 10µH, the peak-to-peak inductor ripples atthe voltage extremes (15V VIN for buck and 2.5V VIN forboost) are:Buck = 251mA peak-to-peak
Boost = 94mA peak-to-peakOne-half of this inductor ripple current must be added tothe highest expected average inductor current in order toselect the proper saturation current rating for the inductor.

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LTC3130/LTC3130-1
APPLICATIONS INFORMATION
To minimize core losses and to prevent high inductor current ripple from tripping the peak current limit before theaverage current limit is reached, an inductor value with a
�IL of less than 500mA P-P should be chosen. For loads
that operate well below current limit, higher inductor ripple
can be tolerated to allow the use of a lower value inductor.
To avoid the possibility of inductor saturation during loadtransients, an inductor with a saturation current ratingof at least 1200mA is recommended for all applications(unless the ILIM pin of the LTC3130 is set low, in whichcase a 650mA rated inductor may be used).
Note that in boost mode, especially at large step-up ratios, the output current capability is often limited by the
total resistive losses in the power stage. These losses
include switch resistances, inductor DC resistance and
PCB trace resistance. Avoid inductors with a high DC
resistance (DCR) as they can degrade the maximum output current capability from what is shown in the Typical
Performance Characteristics section and from the TypicalApplication circuits.
As a guideline, the inductor DCR should be significantly
less than the typical power switch resistance of 350mΩ.
The only exceptions are applications that have a maximum output current much less than what the LTC3130/
LTC3130-1 are capable of delivering. Generally speaking,inductors with a DCR in the range of 0.05Ω to 0.15Ω arerecommended. Lower values of DCR will improve the efficiency at the expense of size, while higher DCR values
will reduce efficiency (typically by a few percent) whileallowing the use of a physically smaller inductor.
Different inductor core materials and styles have an impact
on the size and price of an inductor at any given current
rating. Shielded construction is generally preferred as it
minimizes the chances of interference with other circuitry.
The choice of inductor style depends upon the price, sizing,and EMI requirements of a particular application.
Table 2 provides a wide sampling of inductor families fromdifferent manufacturers that are well suited to LTC3130/
LTC3130-1 applications. However, be sure to check thecurrent rating and DC resistance for the particular value
you need, as not all of the inductor values in a given family
will be suitable.
Table 2. Recommended Inductors
VENDOR

PART NUMBER FAMILY

Coilcraftcoilcraft.com

EPL3015, LPS3314, LPS4012, LPS4018,
XFL3012, XFL4020, MSS4020

Coiltronics
cooperindustries.com

SD3814, SD3118, SD52

Muratamurata.com

LQH43P, LQH44P

Sumidasumida.com

CDRH2D18, CDRH3D14, CDRH3D16,
CDRH4D14

Taiyo-Yuden
t-yuden.com

NR3012T, NR3015T, NRS4012T, NR4018T

TDK
tdk.com

VLF252015MT, VLF302510MT,
VLF302512MT, VLS3015ET, VLCF4018T,
VLCF4020T, SPM4012TToko
tokoam.com

DB318C, DB320C, DEM2815C, DEM3512C,
DEM3518C

Wurth
we-online.com

WE-TPC 2818, WE-TPC 3816

Recommended maximum inductor values and minimum
output capacitor values, for different output voltage
ranges are given in Table 3 as a guideline. These values
were chosen to minimize inductor size while ensuringloop stability over the entire load range of the converter.
Table 3. Recommended Inductor and
Output Capacitor Values
MINIMUM RECOMMENDED OUTPUT CAPACITANCE (μF)
VOUT
(V)

LMAX LTC3130-1/LTC3130
LTC3130(μH) WITH FEED FORWARD PWM AND NO FEED-FORWARD

1 – 2.4

4.7

40

20

2.5 – 3.9

6.8

30

15

4 – 6.5

10

20

10

6.6 – 14

15

20

10

14 – 2515

10

5Note that many applications will be able to use a lower
inductor value, depending on the input voltage range andresulting inductor current ripple. Lower inductor values
will also allow the use of a smaller output capacitor value
without compromising loop stability.

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23

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
Output Capacitor Selection
A low effective series resistance (ESR) output capacitorof 10µF minimum should be connected at the output of
the buck-boost converter in order to minimize output voltage ripple. Multilayer ceramic capacitors are an excellent
option as they have low ESR and are available in small
footprints. The capacitor value should be chosen large
enough to reduce the output voltage ripple to acceptablelevels. Neglecting the capacitor’s ESR and ESL (effectseries inductance), the peak-to-peak output voltage ripple
can be calculated by the following formula, where f is thefrequency in MHz (1.2MHz), COUT is the capacitance in µF,
tLOW is the switch pin minimum low time in µs (0.07µs)
and ILOAD is the output current in Amps:∆VP-P(BUCK) =ILOAD t LOW∆VP-P(BOOST) =

COUT

Volts

ILOAD  VOUT – VIN + tLOW fVIN  Volts
fC
V
OUT

OUT

Examining the previous equations reveal that the output
voltage ripple increases with load current and is generally higher in boost mode than in buck mode. Note thatthese equations only take into account the voltage ripple
that occurs from the inductor current to the output being
discontinuous. They provide a good approximation of theripple at any significant load current but underestimate theoutput voltage ripple at very light loads where the output
voltage ripple is dominated by the inductor current ripple.
In addition to the output voltage ripple generated acrossthe output capacitance, there is also output voltage ripple
produced across the internal resistance of the output
capacitor. The ESR-generated output voltage ripple is
proportional to the series resistance of the output capacitor
and is given by the following expressions where RESR is24

the series resistance of the output capacitor and all otherterms as previously defined:∆VP-P(BUCK) =ILOADRESR∆VP-P(BOOST) =1– tLOW f≅ ILOADRESR VoltsILOADRESR VOUT(

VIN 1– t LOW f)V ≅ ILOADRESR  OUT  Volts
 VIN In most LTC3130/LTC3130-1 applications, an output
capacitor between 10µF and 47µF will work well. To minimize output ripple in Burst Mode operation, or transients
incurred by large step loads, values of 22µF or larger are
recommended.
Input Capacitor Selection
The PVIN pin carries the full inductor current, while the VINpin provides power to internal control circuits in the IC. To
minimize input voltage ripple and ensure proper operation of the IC, a low ESR bypass capacitor with a value ofat least 4.7µF should be located as close to the PVIN pin
as possible. The VIN pin should be bypassed with a 1μF
ceramic capacitor located close to the pin, and Kelvined
to “quiet side” of the primary VIN decoupling capacitor.
Do not tie the VIN pin directly to PVIN pin.
When powered through long leads or from a power sourcewith any significant resistance, an additional, larger value
bulk input capacitor may be required and is generally
recommended. In such applications, a 47µF to 100µF
low ESR electrolytic capacitor in parallel with the 4.7µF
ceramic capacitor generally yields a high performance,
low cost solution.
For applications using the MPPC feature, a minimum CIN
capacitor value of 22µF is recommended. Larger values
can be used without limitation.

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LTC3130/LTC3130-1
APPLICATIONS INFORMATION
Recommended Input and Output Capacitor Types
The capacitors used to filter the input and output of the
LTC3130/LTC3130-1 must have low ESR and must be
rated to handle the AC currents generated by the switching
converter. This is important to maintain proper functioningof the IC and to reduce output voltage ripple. There aremany capacitor types that are well suited to these applications including multilayer ceramic, low ESR tantalum,
OS-CON and POSCAP technologies. In addition, there
are certain types of electrolytic capacitors such as solid
aluminum organic polymer capacitors that are designed
for low ESR and high AC currents and these are also well
suited to some LTC3130/LTC3130-1 applications.

value capacitance or a higher voltage rated capacitor thanwould ordinarily be required to actually realize the intended
capacitance at the operating voltage of the application. X5R
and X7R dielectric types are recommended as they exhibit
the best performance over the wide operating range andtemperature of the LTC3130/LTC3130-1. To verify thatthe intended capacitance is achieved in the application
circuit, be sure to consult the capacitor vendor’s curveof capacitance versus DC bias voltage.
Using the Programmable RUN Function to Operatefrom Extremely Weak Input Sources

Beware of Capacitor DC Bias EffectAnother application of the programmable RUN pin isthat it can be used to operate the converter in a “hiccup”
mode from extremely weak sources. This allows operationfrom sources that can only generate microamps of output
current, and would be far too weak to sustain normal
steady-state operation, even with the use of the MPPC
pin. Because the LTC3130/LTC3130-1 draw only 1.4µA
typical from VIN until they are enabled, the RUN pin can be
programmed to keep the ICs disabled until VIN reaches the
programmed voltage level. In this manner, the input source
can trickle-charge an input storage capacitor, even if it can
only supply microamps of current, until VIN reaches theturn-on threshold set by the RUN pin divider. The converter
will then be enabled, using the stored charge in the input
capacitor to power the converter and bring up VOUT, until
VIN drops below the turn-off threshold, at which point theconverter will turn off and the process will repeat.

Ceramic capacitors are often utilized in switching converter applications due to their small size, low ESR andlow leakage currents. However, many ceramic capacitors
intended for power applications experience a significant
loss in capacitance from their rated value as the DC bias
voltage on the capacitor increases. It is not uncommon fora small surface mount capacitor to lose more than 50%
of its rated capacitance when operated at even half of its
maximum rated voltage. This effect is generally reduced
as the case size is increased for the same nominal value
capacitor. As a result, it is often necessary to use a larger

This approach allows the converter to run from weaksources as small, thin-film solar cells using indoor lighting. Although the converter will be operating in bursts, it
is enough to charge an output capacitor to power low duty
cycle loads, such as in wireless sensor applications, orto trickle-charge a battery. In addition, note that the input
voltage will be cycling (with 10% ripple as set by the UVLO
hysteresis) about a fixed voltage, as determined by thedivider. This allows the high impedance source to operate about the programmed optimal voltage for maximum
power transfer.

The choice of capacitor technology is primarily dictatedby a trade-off between size, leakage current and cost. In
backup power applications, the input or output capacitor
might be a super or ultra capacitor with a capacitancevalue measuring in the Farad range. The selection criteria
in these applications are generally similar except that voltage ripple is generally not a concern.
Some capacitors exhibit a high DC leakage current which
may preclude their consideration for applications that
require a very low quiescent current in Burst Mode operation. Note that ultra capacitors may have a rather high
ESR, therefore a 4.7µF (minimum) ceramic capacitor isrecommended in parallel, close to the IC pins.

3130f

For more information www.linear.com/LTC3130

25

LTC3130/LTC3130-1
APPLICATIONS INFORMATIONIn these “trickle-charge” applications, a larger input capacitor is generally required. If the load on VOUT is extremely
light, such that the available steady-state input power cansustain VOUT, then the input capacitor simply has to haveenough charge to bring VOUT into regulation before VIN
discharges below the falling UVLO threshold (assumingthat the goal is to charge up VOUT in a single “burst” andthen maintain VOUT regulation). In this case, the minimum
value required for CIN can be determined by:
CIN(MIN) >COUT • VOUT 2( η( V – (0.9 • V )))
IN

2

IN

2

where VIN is the programmed rising UVLO threshold andη is the average conversion efficiency, given VIN and VOUT.
It can be seen that a larger COUT capacitor will require alarger CIN capacitor to charge it.
The time required for the CIN capacitor to charge up to the
VIN rising UVLO threshold (starting from zero volts) is:tCHARGE ( sec ) =CIN (µF ) • VIN(UVLO)(ICHARGE (µA ) – 1.4µA –ILEAK (µA ))where ILEAK is the leakage of the input capacitor in µA at
the programmed VIN UVLO voltage.
For applications where VOUT must remain in regulation
during a pulsed load for a given period of time, the input
capacitor value required will be dictated by the programmed
VIN and VOUT, and the duration and magnitude of the output
load current, as given by:
CIN(MIN) >IOUT • VOUT • 2 • t( η( V – (0.9 • V )))
IN

2

IN

2

where CIN is in micro Farads, IOUT is the average load
current in milliamps for duration t in milliseconds. VINis the programmed rising UVLO threshold and η is theaverage conversion efficiency, given VIN and VOUT. This
calculation assumes that the VOUT capacitor has alreadybeen charged, and that the load on VOUT before and after
the load pulse is low enough as to be sustained by theavailable steady-state input power.

26

For example, if VOUT is 5V, with a pulsed load of 25mA
for a duration of 5ms, and VIN has been programmed fora rising UVLO threshold of 12V, then the minimum CIN
capacitor required, assuming a conversion efficiency of
85%, would be 53.7µF, so a 68µF input capacitor would
be recommended.
When using high value RUN pin divider resistors (in theMΩ range) to minimize current draw on VIN, a small noise
filter capacitor may be necessary across the lower divider
resistor to prevent noise from erroneously tripping the
RUN comparator. The capacitor value should be minimized(10pF may do) so as not to introduce a time delay longenough for the input voltage to drop significantly below
the desired VIN threshold. Note that larger VIN decoupling
capacitor values will minimize this effect by providing more
holdup time on VIN.
Use of the EXTVCC Input
As discussed in the Operation section of this data sheet,the LTC3130/LTC3130-1 include an EXTVCC input that canbe used to provide VCC for the IC, allowing start-up and/or operation in applications where VIN is below the VCC
UVLO threshold, all the way down to less than 1V.
Possible sources that could be used to power the EXTVCC
input would include VOUT (if VOUT is programmed for atleast 3.15V and if VIN is at least 2.4V to start), or an independent voltage rail that may be available in the system,
or even a battery.
The requirements for the EXTVCC voltage are that it is aminimum of 3.0V typical, and an absolute maximum of
25V. It must also be able to supply a minimum of 6mAof current. If the source of EXTVCC is not very close to
the IC, then a decoupling capacitor of 4.7µF minimum is
recommended at the EXTVCC pin.
In the case of using a battery to power EXTVCC, the battery
life for continuous steady-state operation in fixed frequency
mode can be estimated by:Battery Life (Hours) = Battery Capacity (mA-Hr)/6mA

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
For example, a 3.6V battery with a capacity of 2600mA‑Hr(2.6A-Hr) could power the IC continuously in fixed
frequency mode for ~433 hours (only about 18 days).
However, if the IC is in Burst Mode operation at light load,
the battery life time will be extended, possibly by ordersof magnitude (depending on the load) since the current
demand when the IC is sleeping will be only 1.6µA typical.
In shutdown, the current draw will be only 0.5µA typical.
For applications where VOUT will be greater than the battery
voltage, and at least 3.6V, a battery and a dual Schottky
diode can be used to get the part started at low VIN. After
start-up, the IC will be powered from VOUT, so there will
be no steady-state current draw on the battery. In thiscase, the battery life may approach its shelf life (even incontinuous fixed frequency operation). In shutdown, there
will be about 0.5uA of current draw from the battery. An
example of this configuration is shown in Figure 5.
+
V

PVIN
VIN
1V TO 25V

– EXTVCC

VOUT

VIN LTC3130/
LTC3130-1
RUN

COUT

VOUT
4V TO 25V

BAT54CEXTVCC
SGND

4.7µF

+

3.6V

3031 F05

Figure 5. Using a Battery Just for Start-Up from Low VIN

Note that during start-up, when VCC is still in UVLO, the IC
chooses the higher of VIN or EXTVCC to power VCC (evenif EXTVCC is below 3.0V). After start-up however, when
VCC has risen above its rising UVLO threshold, the IC
will choose to use the EXTVCC input to power VCC only if
EXTVCC is above 3.0V, typical. This is done to avoid using
EXTVCC at a very low voltage when a higher voltage may
be available at VIN.
Therefore, there could be a situation where the IC would
switch between using EXTVCC during start-up, and VIN as
the source for VCC after start-up. However, if VIN is below
the UVLO threshold, VCC will drop and revert to using
EXTVCC again. This cycling will only occur if VIN is below
the UVLO falling threshold and EXTVCC is greater than the
UVLO rising threshold of 2.4V, but less than 3.0V (andthe part is enabled, with the RUN pin above the accurate
rising threshold). Note that during this time, the IC will be

periodically trying to start switching, as it goes in and out
of UVLO. If EXTVCC is held above 3.0V, this will not occur.
In applications where the VIN and EXTVCC voltages are
such that this scenario could occur, the RUN pin can beused to monitor the EXTVCC input and inhibit operation
whenever EXTVCC is below 3.15V. An example of this isshown in Figure 6.
EXTVCC

+
V

–

2M
VEXT

LTC3130
1.05V

RUN

–
+

ENABLE
SWITCHING

1M
3130 F06

Figure 6. Using the RUN Pin to Set the Minimum Voltage
for EXTVCC to 3.15V

Programming the MPPC Voltage
As discussed in the previous section, the LTC3130/
LTC3130-1 include an MPPC function to optimize performance when operating from voltage sources with relatively
high source resistance. Using an external voltage divider
from VIN, the MPPC function takes control of the average
inductor current when necessary to maintain a minimum
input voltage, as programmed by the user. Referring to
Figure 3:
 R5 
VIN(MPPC) = 1.0V •  1+ 
 R6 
This is useful for such applications as photovoltaic powered converters, since the maximum power transfer point
occurs when the photovoltaic panel is operated at about
75% of its open-circuit voltage. For example, when operating from a photovoltaic panel with an open-circuit voltage
of 5V, the maximum power transfer point will be when
the panel is loaded such that its output voltage is about
3.75V. Referring to Figure 4, choosing values of 2MΩ forR5 and 732k for R6 will program the MPPC function toregulate the maximum input current so as to maintain VIN
at a minimum of 3.73V (typical). Note that if the panel can
provide more power than the application requires, the input
voltage will rise above the programmed MPPC point. Thisis fine as long as the input voltage doesn’t exceed 25V.
3130f

For more information www.linear.com/LTC3130

27

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
For weak input sources with very high resistance (hundredsof Ohms or more), the LTC3130/LTC3130-1 may still draw
more current than the source can provide, causing VIN todrop below the UVLO threshold. For these applications,
it is recommended that the programmable RUN feature
be used, as described in a previous section.
MPPC Compensation and Gain
When using MPPC, there are a number of variables that
affect the gain and phase of the input voltage control loop.
Primarily these are the input capacitance, the MPPC resistor
divider ratio and the VIN source resistance. To simplify thedesign of the application circuit, the MPPC control loop
in the LTC3130/LTC3130-1 is designed with a relatively
low gain, such that external MPPC loop compensation is
generally not required when using a VIN capacitor of atleast 22µF.
The gain from the MPPC pin to the internal control voltage
is about ten, and the gain of the internal control voltage
to average inductor current is about one. Therefore, achange of 60mV a the MPPC pin will result in a change of
average inductor current of about 600mA, which is close
to the full current capability of the IC. So the programmed
input voltage will be maintained within about 6% over thefull current range of the IC (which may be more than that
required by the load).
Sources of Small Photovoltaic Panels
A list of companies that manufacture small solar panels(sometimes referred to as modules or solar cell arrays),suitable for use with the LTC3130/LTC3130-1 is provided
in Table 4.
Table 4. Small Photovoltaic Panel Manufacturers
Sanyopanasonic.net

PowerFilmpowerfilmsolar.com

Ixys
Corporation

ixys.com

G24
Innovations

gcell.com

28

Thermal Considerations
The power switches of the LTC3130/LTC3130-1 are designed to operate continuously with currents up to theinternal current limit thresholds. However, when operating
at high current levels, there may be significant heat generated within the IC. As a result, careful consideration mustbe given to the thermal environment of the IC in order toprovide a means to remove heat from the IC and ensurethat the LTC3130/LTC3130-1 is able to provide its full-rated
output current. Specifically, the exposed die attach padof both the QFN and MSE packages must be soldered toa copper layer on the PCB to maximize the conduction ofheat out of the IC package. This can be accomplished byutilizing multiple vias from the die attach pad connection
underneath the IC package to other PCB layer(s) containing
a large copper plane. A typical board layout incorporatingthese concepts in show in Figure 7.
As described elsewhere in this data sheet, the EXTVCC
pin may be used to reduce the VCC power dissipation
term significantly in high VIN applications, lowering dietemperature and improving efficiency.
If the IC die temperature exceeds approximately 165°C,
overtemperature shutdown will be invoked and all switching
will be inhibited. The part will remain disabled until the dietemperature cools by approximately 10°C. The soft-start
circuit is re-initialized in overtemperature shutdown toprovide a smooth recovery when the IC die temperaturecools enough to resume operation.
Applications with Low VIN and VOUT
Applications which must operate from input voltages ofless that 3V and have an output voltage of 1.8V or less,while operating at heavy loads, will benefit significantly
from the addition of Schottky diode from SW2 to VOUT.
Diodes such as an MBR0530 or equivalent are recommended for these applications.

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
LTC3130

L1

CBST2

CBST1

RPGD

VIN

VOUT

GND

GND
CIN

PGOOD

ILIM

R2 R1
MODE

MPPC

RUN

COUT

CEXT

CVCC

LTC3130-1

L1

CBST2

CBST1

RPGD

VIN

VOUT

GND

GND
CIN

COUT

VS1

MODE

VS2

RUN

MPPC

PGOOD

CEXT

CVCC

8603 F07

Figure 7. Typical 2-Layer PC Board Layout (QFN Package Shown)

3130f

For more information www.linear.com/LTC3130

29

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
22nF
VOC = 5V
VOP = 3.5V

VIN

BST1
PVIN

22nF

4.7µH

SW1

SW2

PV
PANEL

RUN

47µF
1µF

VCC
2M

+

4.7µF

VIN
4.99M

BST2
VOUT
EXTVCCLTC3130

MPPC

PGOOD

ILIM

FB

MODE

VCC
GND

3.4M

PGND

4.7µF

+

1M

100F

VOUT
4.4V
100k

100F

100k

TECATETPL-100/22x45F

3130 F08

Figure 8. Outdoor Solar Panel Powered, 600mA Supercapacitor Charger Using MPPC

22nF

BST1
PVIN

VIN

22nF

10µH

SW1

SW2

VIN
3.6V
Li-SOCI2

+

RUN
10µF

VCC
1µF

LTC3130BST2VOUT
EXTVCC

MPPC

PGOOD

ILIM

FB

1M

10µF
4.02M

200k

PGOOD

VCC

MODE
GND

PGND

10pF

VOUT
24V
20mA

174k

4.7µF
3130 F09

Figure 9. Battery-Powered 24V Converter with 200mA ILIM to Limit Battery Droop

30

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
22nF

BST1
PVIN

VIN
2.4V TO 25V

22nF

10µH

SW1

SW2

VIN
RUN

10µF
VCC
1µF

BST2
VOUT

10µF

EXTVCCLTC3130

MPPC

PGOOD

ILIM

FB

4.99M
249k

VCC

MODE
GND

VOUT
15V
500mA
10pF (V > 15V)
IN

PGND

4.7µF

357k

3130 F10

Figure 10. Wide VIN Range 15V Converter with Burst Mode Operation

22nF

BST1
PVIN

VIN
0.95V TO 25V(2.4V TO START)

22nF

6.8µH

SW1

SW2

22µF

VIN
RUN
10µF

VCC

LTC3130-1

EXTVCC

1M

MPPC
MODE

1µF

VOUT
5V
500mA
(VIN > 5V)

BST2
VOUT

PGOOD

PGOOD

VS1
VS2

VCC
GND

PGND

4.7µF
3130 F11

Figure 11. Low Noise, Wide VIN Range 5V Converter

3130f

For more information www.linear.com/LTC3130

31LTC3130/LTC3130-1
APPLICATIONS INFORMATIONMBR052022nF

12V WALL ADAPTER INPUTIOUT UP TO 600mA WHEN OPERATING FROM WALL ADAPTERIOUT UP TO 500mA WHEN OPERATING FROM USB 3.0 INPUTIOUT UP TO 300mA WHEN OPERATING FROM BATTERY

22nF

6.8µH

B130
USB 3.0 INPUT

BST1
PVIN
VIN

BSS314

RUN
GATE

VIN

10µF

LTC4412
Li-Ion

+

VCC

SW1

SW2

STAT
GND

1M

MPPC
PGOOD

PGOOD

VS1

1µF

CTL

VOUT
5V

22µF

EXTVCCLTC3130-1

MODE

SENSE

BST2
VOUT

VCC

VS2

VCC
GND

PGND

4.7µF
3130 F12

Figure 12. Multiple VIN 5V Out Application, Using the LTC4412 PowerPath™ Controller

22nF

VMPPC = 8V

BST1
PVIN
VIN

VIN

+
10V
TO
14V

698k

10Ω

RUN

22nF

6.8µH
SW1

SW2

LTC3130-1

BST2
VOUT

10µF

VOUT
12V
100mA MINEXTVCC

MPPC

22µF

100k

1µF

MODE

VCC

VS1

PGOOD

VS2

VCC
GND

PGND

4.7µF
3130 F13

Figure 13. 12V Converter Uses MPPC Function to Maintain a Minimum VIN from a Current Limited Source

32

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
APPLICATIONS INFORMATION
22nF

DC SOURCE<0.9V TO 25V(2.4V + VD1
TO START)

D1*

BST1
PVIN
VIN

+

470µF
25V
×2

RUN

4.7µF
VCC

22nF

6.8µH
SW1

SW2

BST2
VOUT
47µF

VOUT
3.3V

EXTVCCLTC3130-1

MPPC
MODE

PGOOD

VS1
VS2

VCC
GND

PGND

4.7µF
3130 F14*D1 PREVENTS DISCHARGE OF INPUT CAPACITOR TO
THE SOURCE. MAY NOT BE REQUIRED IN ALL APPLICATIONS.

Figure 14. 3.3V Converter with "Last Gasp" Hold-Up, Runs Storage Capacitor Down to 0.9V

22nF
BAS70-05

UVLO THRESHOLDS
11.55V/0.95V

BST1
PVIN
VIN

22nF

6.8µH
SW1

SW2

BST2
VOUT
22µF

VOUT
5V

10M
INPUT SOURCES:
RF
AC
PIEZO
COIL-MAGNET

BAS70-06

47µF
16V
CER
×2

VCC

RUN

LTC3130-1

MODE

1M
1µF

EXTVCC

MPPC
PGOOD

VS1
VS2

GND

PGND

VCC
4.7µF

3130 F15*D1 IS REQUIRED WHEN USING THE MSOP PACKAGE.

Figure 15. 5V Converter Operates in Hiccup-Fashion Off of Harvested Energy
Uses PGOOD to Provide Wide UVLO Hysteresis Range
Draws Only 2.5µA From VIN Prior to Start-Up

3130f

For more information www.linear.com/LTC3130

33

LTC3130/LTC3130-1
TYPICAL APPLICATIONS
22nF
VIN
4 Li-Ion

BST1
PVIN
VIN

UVLO = 11.41V
4.99M

SW1

10µF

VCC

SW2

BST2
VOUT
10µF

RUN

+

22nF

6.8µH

VOUT
12V
500mA

EXTVCCLTC3130-1

MPPC
MODE

453k

PGOOD

VS1
VCC
GND

PGND

4.7µF
3130 F16*D1 IS REQUIRED WHEN USING THE MSOP PACKAGE.

Figure 16. 12V Converter with Burst Mode Operation and VIN UVLO

10µH
SW
VIN
VOUT
LTC3525-3.3
SHDN
GND

2.2µF

VOUT1
3.3V
4.7µF

22nF

BST1
PVIN
VIN

VIN

RUN

10µF
ALKALINE +OR NiMH
0.85V to 1.5V

VCC
1µF

22nF

1.5µH

SW1

SW2

LTC3130

BST2
VOUT

MPPC

PGOOD

ILIM

FB

MODE

47µF

EXTVCC

402k
20k

VCC
GND

PGND

100pF

VOUT2
1.2V

4.7µF

2M

3130 F17

Figure 17. Single-Cell 1.2V, 200mA Buck Boost Converter,
Using the LTC3525-3.3 to Provide the EXTVCC Bias Supply

34

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
TYPICAL APPLICATIONS
1μF
22nF

BST1
PVIN
VIN

VIN
<0.9V TO 25V(2.4V TO START)

VCC

MPPC

1µF

MODE

SW2

BST2
VOUT

VOUT
1.80V

47µF

RUN

10µF

22nF

3.3µH

SW1

BAT54S

LTC3130-1

4.7µF

EXTVCC
PGOOD

VS1
VS2

VCC
GND

PGND

4.7µF
3130 F18

Figure 18. Wide VIN Range, Low Noise 1.8V Converter Uses Charge Pump to Generate an EXTVCC Supply

22nF

BST1
PVIN
VIN
RUN

VIN
0.95V TO 25V(2.4V TO START)
10µF

22nF

6.8µH

SW1

SW2

LTC3130BST2VOUT
EXTVCC

VCC

MPPC

PGOOD

200mA 600mA

ILIM

FB

1µF

MODE

47µF

PGND

VOUT
3.6V

2.61M
100k

VCC
GND

15pF

4.7µF

1M

3130 F19

Figure 19. Wide VIN Range 3.6V Converter with Two Programmed Current Limit Levels

3130f

For more information www.linear.com/LTC3130

35

LTC3130/LTC3130-1
PACKAGE DESCRIPTION

Please refer to http://www.linear.com/product/LTC3130#packaging for the most recent package drawings.

UDC Package
20-Lead Plastic QFN (3mm × 4mm)

(Reference LTC DWG # 05-08-1742 Rev Ø)

0.70 ±0.05
3.50 ±0.05
2.10 ±0.05
1.50 REF

2.65 ±0.05
1.65 ±0.05

PACKAGE OUTLINE
0.25 ±0.05
0.50 BSC
2.50 REF
3.10 ±0.05
4.50 ±0.05
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONSAPPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED
3.00 ±0.10

0.75 ±0.05

1.50 REF
19

R = 0.05 TYP

PIN 1 NOTCH
R = 0.20 OR 0.25
× 45° CHAMFER
20
0.40 ±0.10
1

PIN 1
TOP MARK(NOTE 6)4.00 ±0.10

22.65 ±0.10

2.50 REF

1.65 ±0.10(UDC20) QFN 1106 REV Ø

0.200 REF
0.00 – 0.05

R = 0.115
TYP

0.25 ±0.05
0.50 BSC

BOTTOM VIEW—EXPOSED PAD
NOTE:
1. DRAWING IS NOT A JEDEC PACKAGE OUTLINE
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATIONON THE TOP AND BOTTOM OF PACKAGE

36

3130f

For more information www.linear.com/LTC3130

LTC3130/LTC3130-1
PACKAGE DESCRIPTION

Please refer to http://www.linear.com/product/LTC3130#packaging for the most recent package drawings.

MSE Package
16-Lead Plastic MSOP, Exposed Die Pad(Reference LTC DWG # 05-08-1667 Rev F)

BOTTOM VIEW OFEXPOSED PAD OPTION
2.845 ±0.102(.112 ±.004)

5.10(.201)
MIN

2.845 ±0.102(.112 ±.004)

0.889 ±0.127(.035 ±.005)

81

1.651 ±0.102(.065 ±.004)

1.651 ±0.102 3.20 – 3.45(.065 ±.004) (.126 – .136)

0.305 ±0.038(.0120 ±.0015)
TYP

16

0.50
(.0197)BSC

4.039 ±0.102(.159 ±.004)(NOTE 3)

RECOMMENDED SOLDER PAD LAYOUT

0.254(.010)

0.35
REF

0.12 REF

DETAIL “B”
CORNER TAIL IS PART OF
DETAIL “B” THE LEADFRAME FEATURE.
FOR REFERENCE ONLY
9NO MEASUREMENT PURPOSE

16151413121110 90.280 ±0.076(.011 ±.003)
REF

DETAIL “A”
0° – 6° TYP

3.00 ±0.102(.118 ±.004)(NOTE 4)4.90 ±0.152(.193 ±.006)

GAUGE PLANE

0.53 ±0.152(.021 ±.006)
DETAIL “A”

1.10(.043)
MAX

0.18(.007)SEATING
PLANE

0.17 – 0.27(.007 – .011)
TYP

1234567 8

0.50(.0197)BSC

0.86(.034)
REF

0.1016 ±0.0508(.004 ±.002)

MSOP (MSE16) 0213 REV F
NOTE:
1. DIMENSIONS IN MILLIMETER/(INCH)
2. DRAWING NOT TO SCALE
3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS.
MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX
6. EXPOSED PAD DIMENSION DOES INCLUDE MOLD FLASH. MOLD FLASH ON E-PAD SHALLNOT EXCEED 0.254mm (.010") PER SIDE.

3130f

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnectionof its circuits
as describedherein will not infringe on existing patent rights.
For more
informationwww.linear.com/LTC3130

37

LTC3130/LTC3130-1
TYPICAL APPLICATION
Wide VIN Range 5V Converter Uses Small Primary Battery to Guarantee Start-Up at VIN Less Than 1V
with Near Zero Steady-State Battery Current for Up to 10 Year Battery Life
22nF

BST1
PVIN
VIN

VIN
0.95V TO 25V
STOP RUN

RUN

VCC

MPPC

1µF

22nF

6.8µH

SW1

SW2

BST2
VOUT
22µF

LTC3130-1

PGOOD

VS1
VCC

BAT54CEXTVCC

MODE

10µF

VS2
PGND

+

4.7µF

VCC
GND

VOUT
5V

3.6V
TADIRAN TL-4902

4.7µF
3130 TA02

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PART

DESCRIPTION

LTC3129/LTC3129-1

38 Linear Technology Corporation

1630 McCarthy Blvd., Milpitas, CA 95035-7417
For more information www.linear.com/LTC3130(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com/LTC3130

3130f
LT 0816 • PRINTED IN USA

 LINEAR TECHNOLOGY CORPORATION 2016