Intelligent Lighting Family
Product Guide
Part
NumberDescription

Package(s) Available(Lead-free)

Page
No.

LED Backlight Controller ICs for NOTEBOOK / NETBOOK APPLICATIONSOZ9956B

Six String LED Controller

20 QFN7

OZ9956CWhite LED Backlight Controller

20 QFN8

OZ9960High Power LED Controller

12 DFN, 16 SSOP

9OZ9979Six String LED Controller with Phase-Shift 20 QFN
Dimming, Internal MOSFET10

OZ9993

Low Cost White LED Controller

11

6 SOT-23

LED Backlight Controller ICs for MONITOR APPLICATIONSOZ9902

Dual Channel High Power LED Driver

24 SOP, SSOP

12

OZ9906Six String LED Controller

28 E-TSSOP, SOP

13

OZ9908Eight String High Power LED Controller

48 LQFP, 40 QFN14

OZ9961Six String LED Controller

20 E-TSSOP, SSOP

15

OZ9967Six String High Power LED Controller

28 SOP, SSOP, TSSOP16

OZ9997

LED Backlight Controller

24 E-TSSOP, QFN,SOP

17

OZ9998/OZ9998A

Eight String High Power LED Controller

24 E-TSSOP, QFN,
SOP

18

OZ9998B

Four String High Power LED Controller

16 E-SOP, E-TSSOP,
PDIP, QFN, SOP

19

OZ9998H

Four String High Power LED Controller

16 E-SOP, E-TSSOP,
PDIP, SOP

20

GB98A

Four String High Power LED Controller

16 E-SOP, PDIP, SOP

21

LED Backlight Controller ICs for TV APPLICATIONS

2

OZ9902

Dual Channel High Power LED Driver

24 SOP, SSOP

12

OZ9902C

Single Channel High Power LED Driver

16 QFN, SOP

22

OZ9904

Four String LED Controller

28 SOP, SSOP

23

OZ9904A

Eight String LED Controller

40 QFN24

Intelligent Lighting Family
Product Guide
Part
NumberDescription

Package(s)Available(Lead-free)

Page
No.

LED Backlight Controller ICs for TV APPLICATIONS (cont.)
OZ9906Six String LED Controller

28 E-TSSOP, SOP

13

OZ9908Eight String High Power LED Controller

48 LQFP, 40 QFN

14

OZ9908A

Six String High Power LED Controller

28 SOP, TSSOP

25

OZ9908B

Six String High Power LED Controller

32 LQFP, SOP

26

OZ9916Six String High Power LED Controller

44 E-LQFP

27

OZ9920

Four String High Power LED Controller

32 SOP, 30 SSOP

28

OZ9967Six String High Power LED Controller

28 SOP, SSOP,
TSSOP

16

OZ9984

LED Balance Controller

16 SOP

29

OZ9986/
OZ9986A

Phase-Shift, 6 String High Power LED Controller 30 SOP, SSOP/
24 SOP30

OZ9998A

Eight String High Power LED Controller

24 E-TSSOP, QFN,
SOP

18

OZ9998B

Four String High Power LED Controller

16 E-SOP, E-TSSOP,
PDIP, QFN, SOP

19

OZ9998H

Four String High Power LED Controller

16 E-SOP, E-TSSOP,
PDIP, SOP

20

LED Backlight Controller ICs for Small-Size LCD Panels

3

OZ521

Boost Converter Controller

8 E-SOP, SOP

31

OZ532

Compact LED Driver

8 DFN

32

OZ9956B

Six String LED Controller

20 QFN7

OZ9956E

Six String LED Driver Controller

20 QFN33

OZ9960High Power LED Controller

12 DFN, 16 SSOP

9OZ9979Six String LED Controller with Phase-ShiftDimming, Internal MOSFET

20 QFN

10

OZ9993

Low Cost White LED Controller

6 SOT-23

11

Intelligent Lighting Family
Product Guide
Part
NumberDescription

Package(s) Available(Lead-free)

Page
No.

LED Backlight Controller ICs for AUTOMOTIVE/CAR TV/GPS/PND Applications
OZ523

Step Down DC/DC Converter

8 SOP

34

OZ524

Step Down 3A DC/DC Converter

8 E-SOP35

OZ526

White LED Controller

12 DFN36

OZ527

Automotive GPS LED Controller

24 E-TSSOP, QFN

37

OZ528

LCD Bias Supply Controller

28 E-TSSOP, QFN, SOP

38

OZ9960High Power LED Controller

12 DFN, 16 SSOP

9OZ9961Six String LED Controller

20 E-TSSOP, SSOP

15

OZ9965

LED Controller + 2 – DC/DC

28 E-TSSOP39

OZ9990

Four String, High Power, Buck/Boost LED
Driver

24 E-TSSOP40

OZ9993

Low Cost White LED Controller

6 SOT-23

11

OZ9998A

Eight String, High Power LED Controller

24 E-TSSOP, QFN,SOP

18

LED Controller ICs for GENERAL LIGHTING Applications – NON-ISOLATED

4OZ8022Three-Step Dimming

6 SOT-23

41

OZ8022A/
OZ8022B/
OZ8022M

Three-Step Dimming

6 SOT-23

42

OZ8022THigh Power Factor, Three-Step Dimming

16 QFN, 8 SOP

43

OZ8022V

High Power Factor

6 SOT-23

44

OZ8024/OZ8024R

Continuous Dimming

16 QFN, 8 SOP

45

OZ9992/
OZ9992A

Three-Step Dimming

8 SOP

46

Intelligent Lighting Family
Product Guide
Part
NumberDescription

Package(s) Available(Lead-free)

Page
No.

LED Controller ICs for GENERAL LIGHTING Applications – ISOLATEDOZ8027/OZ8027A

High Power Factor/
High Power Factor, Three-Step Dimming

OZ8023/OZ8025High Power Factor, Three-Step Dimming for 8 SOP/
High Power Applications
6 SOT-23

8 SOP

47
48

POWER MANAGEMENT ICs

5

OZ522

Charger + DC/DC PMU

20 SSOP

49

OZ523

Step Down DC/DC Converter

8 SOP

34

OZ524

Step Down 3A DC/DC Converter

8 E-SOP

35

OZ525

Asymmetrical LLC DC/DC Controller

16 SOP

50

OZ529

DC/DC Buck Converter w/USB Power
Switch16 E-SOP, SOP

51

OZ531

Current Mode PWM Controller

8 SOP

52

OZ531A

Current Mode PWM Controller

8 SOP

53

OZ533

Buck Regulator LED Controller

8 E-SOP, SOP

54

Intelligent Lighting
Mission Statement
Be the leading supplier of highly efficient Intelligent Lighting solutions for
power management of electronic products in the Computer, Consumer,
Industrial, Automotive, and Communications markets worldwide.

Products
O2Micro® offers a family of Intelligent Lighting LED controllers for
General Lighting, ranging from bulbs and tubes to high power street/area lighting to automotive applications.
O2Micro’s LED controllers are also ideal for various sizes of Liquid
Crystal Display (LCD) and Power Management Unit (PMU) applications– e.g., Monitors, TVs, Notebooks and Netbooks, PDVDs, Car TVs, GPS,
Digital Photo Frames, and PNDs (Personal Navigation Devices).

CONSUMER Applications

Car TV

LED MONITOR & TV

6

DIGITAL PHOTOFRAME

OZ9956B
FEATURES• High frequency DC/DC power converter controller• Drives up to 6 strings in parallel• Integrated LED current balance control circuit• Wide input voltage range• Up to 2.0MHz switching frequency• External PWM dimming• Over-voltage and over-current protection• Soft start function

GENERAL DESCRIPTIONOZ9956B is a high efficiency, DC/DC controller that drives up to six (6) stringsof LEDs in parallel configuration, with multiple LEDs in each string connected inseries. It is targeted for notebook/netbook applications.
It provides six (6) LED current sense inputs in an “OR” configuration for improved backlight reliability. This allows the backlight to remain functional in theevent that any string (s) is damaged during normal operation.
OZ9956B can receive either an analog signal or an external Pulse Width Modulation (PWM) signal for the dimming control function.
This IC provides an integrated circuit to balance the current flow through each
LED string, as well as, the integrated power MOSFET.

APPLICATIONS		APPLICATION DIAGRAM• Notebook/Netbook
ComputerU.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

7

OZ9956CFEATURES• High frequency DC/DC power converter controller for LEDs
• Drives up to 6 strings in parallel• Integrated LED current balance control circuit• Integrated power MOSFET• Up to 1.5MHz switching operation• Supports phase-shift dimming with adaptive phase control• External PWM dimming control• Output over-voltage and short circuit protection• LED over-current and short circuit protection• Switch over-current protection• Thermal protection• Under-voltage protection

GENERAL DESCRIPTIONThe OZ9956C is a high efficiency, DC/DC controller that drives up to six (6)strings of LEDs in parallel configuration, with multiple LEDs in each string connected in series. It is targeted for notebook/netbook applications.
It provides six (6) LED current sense inputs in an “OR” configuration for improved backlight reliability. This allows the backlight to remain functional in theevent that any string (s) is damaged during normal operation.
OZ9956C supports an external Pulse Width Modulation (PWM) signal for thephase-shifted dimming control function. It provides an integrated circuit tobalance the current flow through each LED string, as well as, an integrated
power MOSFET.

APPLICATIONS		APPLICATION DIAGRAM• Notebook/Netbook
ComputerU.S. Patent #’s 7,498,793; 7,847,783; 8,248,439; and more patents pending.

8

OZ9960
FEATURES• High frequency DC/DC boost converter controller• Integrated power MOSFET• Supports low input voltage• Up to 200mA LED current• External PWM dimming• Open LED protection• MOSFET over-current protection• Soft start function

GENERAL DESCRIPTIONOZ9960 is a high efficiency DC/DC boost converter controller that drives astring of LEDs connected in a serial configuration. It is ideal for small and midsize LCD backlight applications.
OZ9960 supports a wide input range and constant, user-defined operating
frequency for a single string LED application. It receives an external Pulse Width
Modulation (PWM) signal for dimming control.

APPLICATIONS• Notebook/Netbook
Computer
• GPS
• PND

Patents pending.

9		

APPLICATION DIAGRAM

OZ9979
FEATURES• High frequency DC/DC boost converter controller• Integrated power MOSFET, and LED current balance control circuit• Drives up to 6 strings in parallel• Supports external, internal PWM and analog dimming• Enhanced dimming resolution• Supports 6 equal-delay PWM dimming signals• PWM dimming frequency synchronized with external signal• Protection includes: MOSFET over-current, over-voltage, LED short circuit
detection, output short circuit/open diode, and thermal• Soft start function

GENERAL DESCRIPTIONOZ9979 is a high efficiency, DC/DC controller that drives up to six strings ofLEDs connected in parallel configuration; with multiple LEDs in each string connected in series. It is targeted for notebook backlight applications.
The IC provides six (6) LED current sense inputs in an “OR” configuration forimproved backlight reliability. This allows the backlight to remain functional in
the event that any string (s) is damaged during normal operation.

APPLICATIONS		APPLICATION DIAGRAM• Notebook Computer

U.S. Patent #’s 7,498,793; 7,847,783; 8,248,439; and more patents pending.

10

OZ9993
FEATURES• High frequency DC/DC boost converter controller• Supports a single cell Li-Ion battery• Fixed 975kHz switching frequency• Integrated power MOSFET with over-current protection• Output over-voltage protection• Open diode or output short circuit protection• Thermal protection

GENERAL DESCRIPTIONOZ9993 is a high efficiency, DC/DC controller with an integrated power MOSFET that drives one string of LEDs. It provides the user with a low cost solutionthat requires minimum components for the boost regulator and is suitable forapplications requiring a single cell Li-Ion battery.
A soft start feature is provided to minimize in-rush current during start-up.

APPLICATIONS		APPLICATION DIAGRAM• Netbook Computer• PND• Camcorder

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

11

OZ9902
FEATURES• Dual Channel DC/DC converter• Constant current or voltage output• Drives one string of high power LEDs per channel• 180 degrees phase-shift between the two driver outputs• Independent PWM dimming control for each channel• Analog dimming• Constant operation frequency; and Operation frequency synchronization• Power MOSFET over-current protection• Over-voltage protection• Output to return and Output to ground short-circuit protection• Output over load protection• Limited Current Condition (LCC) protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONOZ9902 is a dual, high power LED driver designed to build LED backlight forlarge-size LCD TV applications. It integrates two independently-controlled LED
drivers to achieve optimum efficiency. The drive outputs are phase-shifted by
180 degrees to minimize current ripple in high power applications.
OZ9902 supports independent Pulse Width Modulation (PWM) dimming control
for each channel and common analog dimming control for both channels. It
provides system design flexibility for LCD TV with local dimming or 3D
display mode.

APPLICATIONS		• LCD Monitor• LCD TV

U.S. Patent #7,498,793; and more patents pending.

12

APPLICATION DIAGRAM

OZ9906
FEATURES• Switch-mode DC/DC controller to balance LED current• High current output drive for 6 LED strings• Spread spectrum feature on operating frequency• High efficiency LED current regulation• Supports analog and external PWM dimming• User-defined phase-shift PWM dimming function with 2 to 6 phase options• PWM dimming frequency synchronization• MOSFET over-current protection• LED short circuit protection• User-defined short circuit protection threshold• LED fault status output

GENERAL DESCRIPTIONThe OZ9906 is a high efficiency switch-mode DC/DC controller that drives up to
6 LED strings connected in parallel. It is targeted for large-size monitor and TV
applications.
OZ9906 provides six (6) LED current sense inputs. The IC provides individual
LED current regulation for each LED string. This allows the backlight to remainfunctional in the event that any string (s) is damaged during normal operation.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor• LCD TV

U.S. Patent #’s 7,847,783; 7,919,936; 8,248,439; and more patents pending.

13

OZ9908
FEATURES• Supports 8 strings of 355mA LEDs
• Supports master-slave synchronous operation• Boost converter switching at 180 degree phase-shift between master andslave ICs• Supports analog dimming• Individual PWM dimming for each LED string• Supports over-voltage and over-current protections in application• Supports LED open/short circuit protection• LED fault status output

GENERAL DESCRIPTIONThe OZ9908 is a LED driver controller designed for large-screen LCD backlit
by LEDs. It provides an integrated eight channel LED current regulation control
circuit. Using external balance transistors for each channel, the IC is capable ofdriving a current up to 350mA per LED channel.
OZ9908 provides individual Pulse Width Modulation (PWM) dimming for its
respective LED string. The IC is suitable for LCD TV applications where arealighting technology using local dimming control is applied.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

14

OZ9961
FEATURES• High frequency DC/DC power converter controller• Drives 6 LED strings in parallel• Integrated LED current balance control circuit• Up to 2.35MHz switching frequency• Analog or external PWM or internal LPWM dimming control• Over-current and over-voltage protection• Thermal protection• Open diode and open/short circuit protection• Soft start function

GENERAL DESCRIPTIONThe OZ9961 is a LED controller that drives up to six (6) strings of LEDs in parallel configuration, with multiple LEDs per string connected in series. It provides
six (6) LED current sense inputs in an “OR” configuration to improve backlightreliability. This allows the backlight to remain functional in the event that any
string (s) is damaged during normal operation.
OZ9961 supports either analog, external Pulse Width Modulation (PWM) orinternal Low frequency PWM (LPWM) dimming control.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor• GPS

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

15

OZ9967
FEATURES• High frequency DC/DC boost converter controller• Drives 6 LED strings in parallel• Integrated LED current balance control circuit• Up to 1MHz switching frequency• External PWM or internal LPWM dimming control• LED short circuit protection• Over-current and over-voltage protection• Soft start function

GENERAL DESCRIPTIONThe OZ9967 is an LED controller that drives up to six (6) strings of LEDs in parallel configuration, with multiple LEDs per string connected in series. It provides
six (6) LED current sense inputs in an “OR” configuration to improve backlightreliability. This allows the backlight to remain functional in the event that any
string (s) is damaged during normal operation.
OZ9967 supports external Pulse Width Modulation (PWM) or internal Low
frequency PWM (LPWM) dimming control. Plus, it provides an integrated circuit
to balance the current flow through each LED string. The balance transistors are
external to accommodate different power dissipation resulting from the forward
voltage difference among the LED strings.

APPLICATIONS		• LCD Monitor• LCD TV

U.S. Patent #7,847,783; and more patents pending.

16

APPLICATION DIAGRAM

OZ9997
FEATURES• High power DC/DC boost converter controller• Drives up to 8 LED strings in parallel• External PWM dimming control• Integrated LED current balance control circuit• User-defined string selection• Multi-chip parallel operation for more than 8 LED strings• MOSFET over-current protection• LED short circuit and open string protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONThe OZ9997 is a high efficiency, DC/DC controller that drives up to eight (8)strings of LEDs in parallel configuration, with multiple LEDs in each string connected in series.
The IC provides eight (8) LED current sense inputs in an “OR” configuration to
improve backlight reliability. This allows the backlight to remain functional in theevent that any string (s) is damaged during normal operation.
OZ9997 supports external Pulse Width Modulation (PWM) dimming control, andprovides an integrated circuit to balance the current flow through each
LED string.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

17

OZ9998/9998AFEATURES• High power DC/DC boost converter controller• Drives up to 8 strings in parallel• Integrated LED current balance control circuit• User-defined string selection• External PWM dimming control• Time-shift PWM phase dimming control for low audible noise• Multi-chip parallel operation for more than 8 LED strings• MOSFET over-current protection• LED short circuit and open string protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONOZ9998/98A are high efficiency, DC/DC controllers that drive up to eight (8)strings of LEDs connected in parallel configuration, with multiple LEDs in eachstring connected in series. Each IC provides eight (8) LED current sense inputs
in an “OR” configuration to improve backlight reliability. This allows the backlight to remain functional in the event that any string (s) is damaged during
normal operation.
OZ9998/98A support external Pulse Width Modulation (PWM) dimming control.
Plus, each provides an integrated circuit to balance the current flow througheach LED string.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

18

OZ9998B
FEATURES• High power DC/DC boost converter controller• Drives up to 4 strings in parallel, up to 160mA per string• Integrated LED current balance control circuit• External PWM dimming control• Time-shift PWM phase dimming control for low audible noise• MOSFET over-current protection• LED short circuit and open string protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONOZ9998B is a high efficiency DC/DC controller that drives up to eight strings
connected in parallel configuration, with multiple LEDs in each string connected
in series. It provides four (4) LED current sense inputs in an “OR” configuration
to improve backlight reliability. This allows the backlight to remain functional in
the event that a string (s) is damaged during normal operation.
OZ9998B supports external Pulse Width Modulation (PWM) dimming control.
Plus, it provides an integrated circuit to balance the current flow through each
LED string.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

19

OZ9998H
FEATURES• High power DC/DC boost converter controller• Drives up to 4 high power LED strings• Optimized for high voltage drive output• Integrated 90V transistors for LED current balance control circuit• External PWM dimming control• Up to 50kHz PWM dimming frequency; and 1000:1 PWM dimming ratio• Supports single power train with multiple IC in parallel operation• Power MOSFET over-current protection• LED short circuit and open string protection• LED return to ground short circuit protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONOZ9998H is a high efficiency, high power LED driver controller optimized forlarge-size LCD Monitor and LCD TV applications. It is integrated with a highvoltage MOSFET driver and up to 90V rating current balance transistors. It
can drive up to four (4) strings of high power LEDs connected in parallel configuration.
OZ9998H supports external Pulse Width Modulation (PWM) dimming control.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

20

GB98AFEATURES• Boost converter controller for up to four strings of high power LEDs
• Integrated transistors for LED current balance control circuit• Supports both analog and direct PWM dimming control• Time-shift PWM phase dimming control for low audible noise• Built-in converter for PWM signal to analog dimming control conversion• Wide range dimming control• Supports single power train, multiple-IC parallel operation• Power MOSFET over-current protection• LED short circuit and open string protection• LED return to ground short circuit protection• Thermal protection

GENERAL DESCRIPTION
GB98A is a high efficiency, high power LED driver controller that provides highvoltage MOSFET driver for the boost converter. It can drive up to four stringsof LEDs at 250mA current rating. It also supports up to 400mA pulsing current
for applications.
GB98A receives external Pulse Width Modulation (PWM) signal input for dimming control.

APPLICATIONS		APPLICATION DIAGRAM• LCD Monitor• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

21

OZ9902C
FEATURES• Constant current or voltage output• Drives one string of high power LEDs
• 0% to 100% PWM dimming control• Analog dimming control• Constant operation frequency• Power MOSFET over-current protection• Over-voltage protection• Output to return and Output to ground short circuit protection• Output over load protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONOZ9902C is a single channel, high power LED driver designed for LED backlightapplications used in large-size LCD TVs.
The controller supports wide range, direct Pulse Width Modulation (PWM) dimming control and analog dimming control for LED string forward current.

APPLICATIONS		• LCD TV

U.S. Patent #7,498,793; and more patents pending.

22

APPLICATION DIAGRAM

OZ9904
FEATURES• Supports up to 4 strings• Up to 355mA LED current per string• Supports external and internal PWM dimming control• Supports analog dimming• Over-voltage and over-current protections in applications• Supports LED open/short circuit protections in applications• LED fault status output

GENERAL DESCRIPTIONThe OZ9904 is a LED driver controller optimized for large screen LED backlight
LCD TV applications. It provides an integrated four-channel LED current control
circuit. In application, it controls external balance transistors to maintain the current balance among LED strings.
OZ9904 supports both internal and external Pulse Width Modulation (PWM)
dimming methods for brightness control of LCDs for various system applications. The internal PWM dimming signal can also be synchronized with the vertical sync signal of the LCD display.
The IC further supports an analog dimming control function, which adjusts the
LED current amplitude of all the four ISEN channels simultaneously.

APPLICATIONS		APPLICATION DIAGRAM• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

23

OZ9904AFEATURES• Drives up to 8 strings of LEDs
• Up to 350mA LED current per string• Supports two boost converters in parallel• 180 degree phase-shift between the two drive outputs• Provides two sets of PWM dimming control• Built-in 180 degree phase-shift PWM dimming control synchronization• Supports analog dimming• Over-voltage and over-current protection• Supports LED open/short circuit protection• LED fault status output

GENERAL DESCRIPTIONOZ9904A is a high performance LED driver controller optimized for large screen
LED backlight LCD TV applications.
It provides two high voltage gate drive signals for the boost converters, with180° phase-shift between the two signals. The IC minimizes input and output
current ripple, and provides a flexible design using only one drive signal for lowpower applications through pin DRVSEL.
OZ9904A supports both internal and external Pulse Width Modulation (PWM)
dimming interfaces for various system configurations.

APPLICATIONS		APPLICATION DIAGRAM• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

24

OZ9908A
FEATURES• Drives up to 6 strings of LEDs
• Up to 350mA LED current per string• Multiple IC parallel operation with power train sharing• Primary side regulation application• Analog dimming control• Individual PWM dimming for every 3 strings• Over-voltage and over-current protection• LED open/short circuit protection• LED fault status output

GENERAL DESCRIPTIONThe OZ9908A is a high performance LED driver controller optimized for large
screen LED backlight LCD TV applications. It provides an integrated six-channel
LED current regulation control circuit. Using external balance transistors foreach channel, the IC is capable of driving a current up to 350mA per LED
channel.
OZ9908A provides two external Pulse Width Modulation (PWM) dimming interfaces for the six LED strings. Each PWM signal controls the brightness of three
LED strings. This feature is suitable for LCD TV applications using a scanningbacklight or 3-dimensional display mode functions.

APPLICATIONS		APPLICATION DIAGRAM• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

25

OZ9908B
FEATURES• Drives up to 6 strings of LEDs
• Up to 350mA LED current per string• Supports multiple IC operation synchronization• Boost drive outputs 180 degree phase-shift between master and slave ICs• Analog dimming control• Individual PWM dimming for each string• Over-voltage and over-current protection• LED open/short circuit protection• LED fault status output

GENERAL DESCRIPTIONThe OZ9908B is a high performance LED driver controller optimized for large
screen LED backlight LCD TV applications. It provides an integrated six-channel
LED current regulation control circuit. Using external balance transistors foreach channel, the IC is capable of driving a current up to 350mA per LED
channel.
OZ9908B provides 6 individual external Pulse Width Modulation (PWM) dimming
interfaces for its respective LED string. The IC is suitable for LCD TV applications using a local-dimming control backlight.
When using multiple ICs, the operating frequency can be synchronized with a
180° phase-shift between the drive outputs of each IC. These features greatly
reduce the interference between ICs.

APPLICATIONS		APPLICATION DIAGRAM• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

26

OZ9916
FEATURES• Dual drive outputs with 180 degree phase-shift for boost controllers• Drives up to 6 strings of high power LEDs
• Built-in 6-channel, 90V, 1A MOSFETs for LED current regulation• Inductor-less switching mode LED current balance control• Individual PWM dimming for each string• Wide range analog dimming control• Synchronized operation of multiple ICs• Feed forward compensation function• Over-voltage and over-current protection• LED open/short circuit protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONThe OZ9916 is a high performance LED driver controller optimized for large
screen LED backlight LCD TV applications. It provides an integrated six-channel
LED current regulation control circuit. Using O2Micro’s proprietary design ofswitching mode LED current regulation without inductors, this architecture
provides up to 400mA average current and up to 1A pulsed current for each
LED string.
OZ9916 provides six individual Pulse Width Modulation (PWM) dimming interfaces for its respective LED string. This IC is suitable for LCD TV applications
where a local-dimming control or scan mode backlight applies.

APPLICATIONS		APPLICATION DIAGRAM• LCD TV

U.S. Patent #’s 8,044,609; 8,237,379; 8,253,352; and more patents pending.

27

OZ9920FEATURES• Drives up to 4 strings of LEDs
• High voltage gate drive for the boost converter• Two blocks individual PWM dimming control for 3D TVs• Internal PWM dimming control synchronization with VSYNC• 10:1 analog dimming ratio• Up to 1000:1 external PWM dimming ratio• Output over-voltage protection• Thermal protection• LED open/short circuit protection• Open-diode protection in boost converter

GENERAL DESCRIPTIONThe OZ9920 is a LED driver controller optimized for large screen LED backlight,
global and/or 3-dimensional TV applications. It provides a high voltage gate
driver for the boost converter, which is designed to drive high voltage power
MOSFETs.
It provides an integrated four-channel LED current regulation control circuit
through the use of external high voltage N-channel MOSFETs.
OZ9920 supports both internal and external Pulse Width Modulation (PWM)
dimming interfaces for various system applications. The internal PWM dimming
signal can be synchronized with the VSYNC signal of the LCD display.

APPLICATIONS		APPLICATION DIAGRAM• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

28

OZ9984
FEATURES• Drives up to 4 LED strings in parallel• Integrated LED current balance control circuit• Multi-chip parallel operation• Analog dimming control• Over-voltage protection (OVP)• User-defined LED short circuit protection• Soft start function

GENERAL DESCRIPTIONOZ9984 is a high efficiency LED driver IC that works in conjunction with a primary side external Pulse Width Modulation (PWM) controller for offline, isolated
LED lighting application. It has four (4) LED current sense inputs in an “OR”
configuration to ensure uniform lighting of the LEDs. It can drive up to 4 stringsof LEDs in parallel and up to 9 LEDs per string connected in series.
OZ9984 supports up to 350mA of LED current per string. It is designed in sucha way that if any LED string is damaged during normal operation, the remaining
string (s) continue normal operation. Multi-chip parallel operation supports additional LED strings.

APPLICATIONS		APPLICATION DIAGRAM• LCD TV
• General Lighting

U.S. Patent #’s 7,847,783; 8,084,960; and more patents pending.

29

OZ9986/9986A
FEATURES• OZ9986: Boost and Buck converter• OZ9986A: Buck converter• High efficiency DC/DC converter controller for LEDs
• Drives up to 6 strings in parallel; number of LEDs in series limited byexternal MOSFET(s) rating• High efficiency LED current balance function• User-selectable, phase-shift PWM dimming function with 3, 4, 5 and6 phases• PWM dimming control signals synchronized with external signal• Over-voltage and over-current protection• Soft start function

GENERAL DESCRIPTIONOZ9986/86A are high efficiency, DC/DC controllers that drive up to six (6) strings
connected in parallel configuration, with multiple LEDs in each string connected
in series. Each is targeted for large-size monitor and TV applications.
Each IC provides six (6) LED current sense inputs in an “OR” configuration to
improve backlight reliability. This allows the backlight to remain functioning in
the event that any string (s) is damaged during normal operation.
OZ9986/86A support internal Pulse Width Modulation (PWM) dimming control,
where the PWM dimming signal is phase-shifted by 60 degrees per channel
when all 6 channels are connected. This proprietary feature significantly enhances the system performance.

APPLICATIONSAPPLICATION DIAGRAMS• LCD Monitor• LCD TV

U.S. Patent #’s 7,498,793; 7,847,783; 7,919,936; 8,248,439; and more patents pending.

30

OZ521FEATURES• Supports wide-range operating voltage• Integrated with a 50V/2A power MOSFET• Supports an optional spread-spectrum switching frequency• In applications:- Supports either constant-voltage or constant-current output- Protection includes: output over-voltage, power MOSFET over-current,
over-temperature, and open rectifier diode- Low standby current

GENERAL DESCRIPTIONOZ521 is a boost converter controller suitable for LED lighting or general purpose DC/DC converter applications.
It integrates a 50V/2A MOSFET as the switch and compensation components
for the boost converter to optimize the cost/performance of applications. In applications, the operating frequency is user-selectable.

APPLICATIONS• LED Lighting• Tablet• Cell Phone

Patents pending.

31		

APPLICATION DIAGRAMOZ532FEATURES• High efficiency controller for boost converter• Supports single-cell Li-Ion battery operation• Drives up to 10 LEDs in series• Integrated power MOSFET• Integrated load-disconnection switch• Supports 100:1 analog dimming ratio• Self-adaptive operating frequency, optimizing efficiency• Protection includes: output over-voltage and over-current, LED short circuit
to ground, and IC over-temperature• Output capacitor discharge function in shutdown mode
• Low standby current

GENERAL DESCRIPTIONOZ532 is a controller designed for boost converter LED driver applications. It
integrates a power MOSFET and drives single-string LEDs in applications.
OZ532 provides a compact solution to the applications that require minimum
components for the boost regulator. It is suitable for portable device applications requiring a single-cell Li-Ion battery.
This IC accepts an external Pulse Width Modulation (PWM) signal to perform
dimming control.

APPLICATIONS		• LED Lighting• Tablet• Cell Phone

U.S. Patent #7,471,144; and more patents pending.

32

APPLICATION DIAGRAM

OZ9956E
FEATURES• Highly integrated LED driver controller• 2.5V – 33V input voltage range• Drives up to 6 strings of LEDs in parallel• Up to 30mA current per string• Built-in LED current balance control circuit• Integrated power MOSFET• Built-in 20kHz PWM dimming control eliminates audible noise• Supports external PWM dimming control• 100:1 dimming ratio at 20kHz PWM frequency• Protection: over-voltage, over-current, thermal, and open rectifier diode

GENERAL DESCRIPTIONThe OZ9956E is a highly efficient, integrated LED driver controller designed for
middle power LCD backlight applications. Featuring a very wide operational
input voltage range, it works as a universal solution for applications powered by
one or multiple Li-Ion battery cells or those directly powered by an adapter.
It provides six (6) LED current sense inputs in an “OR” configuration for improved backlight reliability. This allows the backlight to remain functional in theevent that any string (s) is damaged during normal operation.
OZ9956E accepts external Pulse Width Modulation (PWM) dimming signals toperform either directly controlled external or fixed 20kHz internal dimming function.

APPLICATIONS		APPLICATION DIAGRAM• Notebook/Netbook
ComputerU.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

33

OZ523
FEATURES• Supports constant voltage or constant current applications• 1.5A continuous output current• 0.25Ω internal Power MOSFET• Stable control loop
• VOUT from 0.8V to 0.9*VIN• Soft start function• Fixed switching frequency• Low current shutdown mode
• Over-current and thermal protection

GENERAL DESCRIPTIONThe OZ523 is a fast response PWM controller using minimum external components to achieve control loop stability in DC/DC and LED driver applications. It
supports both constant voltage and constant current applications. OZ523 canoperate in constant current mode to drive high power LED applications.
OZ523 is a non-synchronous step down DC/DC converter with a 0.25Ω integrated MOSFET. It supports a 1.5A continuous load current with up to 3.2A peakcurrent. The output voltage can be user-defined from 0.8V up to 0.9*VIN using a
feedback resistor divider.

APPLICATIONS		• General Purpose DC/DC
Converter• High Power LED DriverPatents pending.

34

APPLICATION DIAGRAMOZ524FEATURES• Supports constant voltage or constant current applications• 3.0A continuous output current• 0.12Ω internal Power MOSFET• Stable control loop
• VOUT from 0.8V to 0.9*VIN• Soft start function• Fixed switching frequency• Low current shutdown mode
• Over-current and thermal protection

GENERAL DESCRIPTIONThe OZ524 is a fast response PWM controller using minimum external components to achieve control loop stability in DC/DC and LED driver applications. It
supports both constant voltage and constant current applications. OZ524 canoperate in constant current mode to drive high power LED applications.
OZ524 is a non-synchronous step down DC/DC converter with a 0.12Ω integrated MOSFET. It supports a 3.0A continuous load current with up to 4.7A peakcurrent. The output voltage can be user-defined from 0.8V up to 0.9*VIN using a
feedback resistor divider.

APPLICATIONS		• General Purpose DC/DC
Converter• High Power LED DriverPatents pending.

35

APPLICATION DIAGRAMOZ526FEATURES• High frequency DC/DC power converter for LEDs
• Integrated power MOSFET• Integrated LED current balance control circuit• User-defined operation frequency• Drives 1 or 2 strings• External PWM and Analog dimming control• Converter output over-voltage protection• Internal power MOSFET over-current protection• Over-current protection for each string• Output short circuit detection• Open diode and thermal protection

GENERAL DESCRIPTIONThe OZ526 is a high efficiency DC/DC controller with an integrated power
MOSFET that drives one string or two LED strings in parallel configuration, withmultiple LEDs connected in series. It is targeted for netbook and PND (Personal
Navigation Device) backlight applications.
OZ526 provides two LED current sense inputs in an “OR” configuration forimproved backlight reliability. This allows the backlight to remain functioning in
the event that any string(s) is damaged during normal operation. The controller receives an external Pulse Width Modulation (PWM) signal for the dimming
control function.

APPLICATIONS		APPLICATION DIAGRAM

• GPS
• PND

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

36

OZ527FEATURES• High power DC/DC power converter• Integrated Power N-Channel MOSFET• Integrated LED current balance control circuit• Drives up to 6 strings in parallel• User-defined string selection• Time-shift PWM phase dimming control for low audible noise• Operation frequency synchronization• LED open string protection• Output short circuit or open diode protection• LED short circuit protection• MOSFET over-current protection• Shutdown under abnormal condition protection• Thermal protection• LED fault status output

GENERAL DESCRIPTIONThe OZ527 is a high efficiency DC/DC controller that drives up to six strings
connected in parallel configuration with multiple LEDs in each string connected
in series.
OZ527 provides 6 LED current sense inputs in an “OR” configuration to improvebacklight reliability. This allows the backlight to remain functioning in the eventthat a string(s) is damaged during normal operation.
OZ527 supports external Pulse Width Modulation (PWM) dimming control.

APPLICATIONS		APPLICATION DIAGRAM• GPS

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

37

OZ528FEATURES• High power DC/DC power
converter• Operation frequency
synchronization• Optional spread spectrum
operation frequency• Thermal, over-current, and overload protection• Abnormal pulled-up output
protection• LED fault status output

Two Independent Boost
Converters• Integrated power MOSFET• Current mode control• Wide output range: up to 25.0V• Adjustable power on/off delay time
• Soft start function
Negative Charge Pump
• Voltage mode control• Adjustable power on/off delay time

Buck Converter• Integrated power MOSFET• Current mode control• Soft start function

GENERAL DESCRIPTIONThe OZ528 is a LCD panel bias power supply controller, suitable for GPS application. It generates four voltage rails for a TFT LCD panel. It includes a boost
converter to provide the source voltage, buck converter to provide the logic
voltage for the system, boost converter for positive gate voltage and a negative
charge-pump driver to provide adjustable regulated output voltages to bias the
TFT panel.
OZ528 has power-on sequencing. The buck converter is the first to start after
the IC is enabled. Two boost converters and a negative charge-pump are enabled when their corresponding TIMER reaches approximately 2.0V.

APPLICATIONS		• GPS

Patents pending.

38

APPLICATION DIAGRAM

OZ9965
FEATURES• Integrated LED controller and two(2) DC/DC converters• User-defined operation frequency• Wide input voltage range• Thermal protection• User-defined shutdown delay time
• LED fault status output
LED Controller• User-defined boost topology orbuck-boost topology• Current mode control• Drives up to 4 strings of LEDs
in parallel• User-defined string selection• Integrated LED current balance
control circuit• External PWM dimming control• LED open string and short circuit
protection

LED Controller (cont.)• MOSFET over-current protection• Over load protection• Output short circuit or open diodeprotection
Boost Converter• Current mode control• Over-voltage protection• MOSFET over-current protection• Over load protection• Soft start function
General Purpose Converter• User-defined negative buck-boost
or buck topology• Voltage mode control• Over-voltage and over loadprotection• Soft start function

GENERAL DESCRIPTIONThe OZ9965 is a wide input range, multi-output, power management controller for small panel LCD applications. It controls the DC/DC power conversion
from a single input supply voltage to provide the power needed to drive an LED
backlight module, source drivers and gate drivers used in a LCD application.
OZ9965 includes a high power LED driver controller, a boost converter, and one
general purpose converter that can be configured into either a buck or negative
buck-boost converter.

APPLICATIONS		
• Car TV
• GPS

U.S. Patent #7,847,783; and more patents pending.

39

APPLICATION DIAGRAM

OZ9990
FEATURES• High power DC/DC power converter controller• Drives up to 4 strings in parallel• Integrated LED current balance control circuit• User-defined string selection• Operation frequency synchronization• External PWM dimming control• Time-shift PWM phase dimming control for low audible noise• LED open string protection• Output short circuit and open diode protection• LED short circuit protection• MOSFET over-current protection• Thermal protection• LED fault status output• Soft start function

GENERAL DESCRIPTIONOZ9990 is a LED controller that drives up to four (4) strings connected in parallel
configuration, with multiple LEDs per string connected in series. It provides four(4) LED current sense inputs in an “OR” configuration to improve backlightreliability. This allows the backlight to remain functioning in the event that any
string(s) is damaged during normal operation.
OZ9990 supports external Pulse Width Modulation (PWM) dimming control,
and provides an integrated circuit to balance the current flow through each LED
string.

APPLICATIONS		APPLICATION DIAGRAM• Car TV
• GPS

U.S. Patent #’s 7,498,793; 7,847,783; and more patents pending.

40

OZ8022FEATURES• Quasi-resonant converter controller for high brightness LEDs
• Low start-up and operating current, maximizing conversion efficiency• Peak current mode control simplifies circuit design• Under-voltage lockout with hysteresis• Minimum off-time control for light-load operation, maximizing efficiency• Provides complete protection functions:- Maximum gate drive output at 19.5V- Over-voltage for IC bias voltage- Cycle-by-cycle current limit at current sense- LED short circuit- Output over-voltage and internal thermal

GENERAL DESCRIPTIONOZ8022 is a controller for Buck converters that use quasi-resonant conversion
technology. It can be used to drive high brightness LEDs in offline applications.
The controller is implemented with compensated peak current mode control toregulate the average LED current.
The operation of the Buck converter is between the continuous and discontinuous mode of the inductor current. During a light-load condition, it provides aminimum off-time scheme to maximize the operating efficiency.

APPLICATIONS• General Lighting

Patents pending.

41		

APPLICATION DIAGRAM

OZ8022A/8022B/8022M
FEATURES• OZ8022A: Three-step forward, 100%-60%-20%, analog dimming control
using wall switch• OZ8022B: Three-step reverse, 20%-60%-100%, analog dimming control
using wall switch• OZ8022M: Three-step night light, 100%-40%-2.5%, analog dimming control
using wall switch• Quasi-resonant converter controller for high brightness LEDs
• Low start-up and operating current, maximizing conversion efficiency• Peak current mode control simplifies circuit design• Under-voltage lockout with hysteresis• Minimum off-time control for light-load operation, maximizing efficiency- Provides complete protection functions:- Maximum gate drive output at 19.5V- Over-voltage for IC bias voltage- Cycle-by-cycle current limit- LED short circuit; output over-voltage; and internal over-temperature

GENERAL DESCRIPTIONThe OZ8022A/22B/22M are controllers for Buck converters that use quasi-resonant conversion technology. Each can be used to drive high brightness LEDs in
offline applications.
OZ8022A/22B/22M provide proprietary Free Dimming technology to control LED
brightness using a non-dimming ON/OFF wall switch.

APPLICATIONS		• General Lighting

U.S. Patent #8,044,608; and more patents pending.

42

APPLICATION DIAGRAM

OZ8022T
FEATURES• Three-step analog dimming control using wall switch• Supports high power factor and low THD for residential and commercial
lighting applications• Quasi-resonant converter controller for high brightness LEDs
• Built-in high voltage start-up circuit• Under-voltage lockout with hysteresis• Minimum off-time control for light-load operation, maximizing efficiency• Provides complete protection functions:- Maximum gate drive output and clamp- Over-voltage for IC bias voltage- Cycle-by-cycle current limit- LED short circuit; output over-voltage; and internal thermal

GENERAL DESCRIPTIONThe OZ8022T is a controller for Buck converters that use quasi-resonant conversion technology. It can be used to provide regulated current for high brightness LEDs with power factor correction in offline applications.
OZ8022T provides proprietary Free Dimming technology to control LED brightness using a non-dimming ON/OFF wall switch.

APPLICATIONS		• General Lighting

U.S. Patent #8,044,608; and more patents pending.

43

APPLICATION DIAGRAM

OZ8022VFEATURES• Quasi-resonant converter controller for high brightness LEDs
• Supports high power factor for LED lighting applications• Low start-up and operating current, maximizing conversion efficiency• Voltage-mode control simplifies circuit design• Under-voltage lockout with hysteresis• Minimum off-time control for light-load operation, maximizing efficiency• Provides complete protection functions:- Maximum gate drive output and clamp- Over-voltage for IC bias voltage- Cycle-by-cycle current limit- LED short circuit; output over-voltage; and internal thermal

GENERAL DESCRIPTIONThe OZ8022V is a controller for Buck converters that use quasi-resonant conversion technology. It can be used to drive high brightness LEDs with power
factor correction in offline applications. The Buck converter operates between
the continuous and discontinuous modes of inductor current.

APPLICATIONS• General Lighting

Patents pending.

44		

APPLICATION DIAGRAM

OZ8024/8024R
FEATURES• OZ8024: Proprietary continuous forward PWM dimming technology using
wall switch• OZ8024R: Proprietary continuous reverse PWM dimming technology using
wall switch• Quasi-resonant converter controller for high brightness LEDs
• Low standby and operating current• Peak current mode control simplifies circuit design• Under-voltage lockout with hysteresis• Minimum off-time control at high-input voltage operation condition• Provides complete protection functions:- Maximum gate drive output and clamp- Over-voltage for IC bias voltage- Cycle-by-cycle current limit- LED short circuit; output over-voltage; and internal thermal

GENERAL DESCRIPTIONThe OZ8024/24R are controllers for Buck converters that use quasi-resonant
conversion technology to provide regulated power for high brightness LEDs in
offline applications.
Each IC provides patented Free Dimming technology to control LED brightness
using a non-dimming ON/OFF wall switch. End-users can simply select adesired LED brightness level from high-to-low (OZ8024) or low-to-high(OZ8024R).

APPLICATIONS		• General Lighting

U.S. Patent #8,076,867; and more patents pending.

45

APPLICATION DIAGRAM

OZ9992/9992AFEATURES• Quasi-resonant AC/DC converter controller for high brightness LEDs
• Three-step analog dimming control using wall switch• Low start-up and operating current, maximizing conversion efficiency• Peak current mode control simplifies circuit design• Under-voltage lockout with hysteresis• Minimum off-time control for light-load operation, maximizing efficiency• Constant output power for universal AC input• Provides complete protection functions:- Maximum gate drive output at 18.0V- Over-voltage for IC bias voltage- Cycle-by-cycle current limit- LED short circuit; output over-voltage; and internal thermal

GENERAL DESCRIPTIONOZ9992/92A are controllers for offline AC/DC flyback converter applications
that use quasi-resonant power conversion technology. One application using
OZ9992/92A drives high power LEDs using compensated peak current mode
control to regulate the average LED current.
OZ9992/92A require very low start-up current, which maximizes the efficiency ofthe converter. Each IC provides a proprietary Free Dimming technology using a
non-dimming ON/OFF wall switch.

APPLICATIONS		• General Lighting• Power Adapter/Battery
Charger• TV/Monitor Power
Supplies

U.S. Patent #8,044,608; and more patents pending.

46

APPLICATION DIAGRAM

OZ8027/8027A
FEATURES• OZ8027A: Three-level analog dimming control using wall switch• Primary side control, AC/DC converter controller• High power factor with wide range input voltage• Constant current output• Fixed operation frequency• Built-in high voltage start-up circuit• Compatible with neon indicators in wall switch• Provides complete protection functions:- VDD over-voltage- VDD under-voltage lockout with hysteresis- Open and Short LED- Primary side cycle-by-cycle current limit- Maximum gate drive output and clamp- Over-temperature

GENERAL DESCRIPTIONThe OZ8027/27A are primary side control, LED driver controllers. Each can beused in high power factor AC/DC converter applications. Each IC operates at
a fixed frequency of 50kHz with discontinuous current mode in flyback circuit
topology.
OZ8027/27A work with neon indicators in a traditional wall switch, without
interference.

APPLICATIONS		APPLICATION DIAGRAM• General Lighting

U.S. Patent #’s 8,044,608; 8,076,867; and more patents pending.

47

OZ8023/8025
FEATURES – OZ8023• Quasi-resonant converter
controller• Built-in high voltage start-up
circuit• Voltage-mode control simplifies
circuit design• Under-voltage lockout withhysteresis• Minimum off-time control for
light-load operation, maximizing
efficiency• Excellent line-voltage regulation• Provides complete protection
functions:- Clamped gate drive output- Over-voltage for IC bias voltage- Cycle-by-cycle current limit- Output short circuit; over load;
output over-voltage; andinternal thermal

FEATURES – OZ8025• Secondary side LED controller• Three-step analog dimming
control using wall switch• Low operating current• Provides complete protection
functions:- VDD over-voltage- Output over-voltage- Internal thermal

GENERAL DESCRIPTIONThe OZ8023 is a voltage-mode, quasi-resonant converter controller suitable foroffline AC/DC flyback converter applications. It can be used as a single-stage
power factor correction controller for an isolated power supply or LED driverapplications.
The OZ8025 is a controller for an isolated LED driver application. It provides a
proprietary three-step Free Dimming technology to control LEDs using an ON/
OFF wall switch.

APPLICATIONS		• Isolated LED Driver

U.S. Patent #8,044,608; and more patents pending.

48

APPLICATION DIAGRAMOZ522FEATURES
Charger• 550KHz switching mode charger
for 1 – 4 cell Li-Ion or Li-Polymer
batteries• Supports fast charge mode
• Wake-up charging function for
discharged batteries• Built-in charge termination
function• Internal safety timer for charger• 92% efficiency• Automatic battery recharge• 1% constant voltage accuracy• Charge status indication by LED• Battery absence detection

DC/DC Converters• Two switch mode buck converters
with under-voltage protection• 2% voltage accuracy• Output protection:- Over-current for each DC/DC
converter- Over-voltage lockout on adapter
voltage- Under-voltage lockout on battery
voltage• Output voltage range of 1.0V to
5.5V• Integrated soft start function, 4ms
soft start function at start-up• ON/OFF control pin

GENERAL DESCRIPTIONThe OZ522 is a charger plus DC/DC Power Management Unit (PMU). It provides
a complete charging algorithm to control 1 – 4 cell Li-Ion batteries, used in Portable DVDs (PDVDs), and other portable electronic equipment.
It delivers a wake-up charging current for discharged batteries followed bya fast charging current to minimize the charging time, and keeps the battery
regulation voltage within 1% accuracy. A battery temperature sensing scheme
allows the battery to be charged within a user-defined temperature range. The
switch mode charger allows use of low AC adapter voltage at high efficiency.

APPLICATIONS		APPLICATION DIAGRAM• PDVD

U.S. Patent #’s 7,268,520; 7,977,911; and more patents pending.

49

OZ525FEATURES• Asymmetrical switch mode DC/DC Controller• Voltage mode PWM control with adjustable drive output sequence• Complementary drive architecture supporting various topologies• Highly customizable driver sequence to minimize switching loss
• Complete protection features:- Over-Voltage Protection (OVP) via VVD pin- Two-level Over-Current Protection (OCP) via CS pin- Over-Temperature (thermal) protection (OTP) via OTP pin- Brownout Protection via BO pin- Open loop Protection (OLP) via FB pin- Adjustable shutdown delay timer via TIMER pin• Fast line feed forward compensation• Adjustable start-up delay time to reduce excessive voltage stress to powercomponents• User-defined soft start time

GENERAL DESCRIPTIONThe OZ525 is an energy efficient, switched mode DC/DC controller designed for
Switched Mode Power Supply (SMPS) applications, using a half-bridge topology. High level integration and distinctive features result in a cost-effective power
supply design, requiring few external components.
The controller provides complementary Pulse Width Modulation (PWM) control
that enables the designer to customize the drive sequence. Such customization,
through dedicated pins, ensures high efficiency and performance in a power
supply system by minimizing switching loss.

APPLICATIONS• General Purpose
AC/DC Converter

Patents pending.

50		

APPLICATION DIAGRAMOZ529FEATURES
DC/DC Buck Converter• Integrates 40V, 3A N-Channel
power MOSFET• Adjustable operation frequency
range 200kHz – 800kHz• Operation frequency
synchronization• System power input under-voltage
lockout• Adaptive output voltage following
USB output requirement• Thermal protection

USB Power Switch• Independent ON/OFF control• Sustains up to 40V input voltage
stress• Up to 1.5A output current
capability• Adjustable over-current limit
threshold• Built-in soft start function• Output voltage vs. load current
compensation• Reverse current protection under
shutdown condition• USB fault status output

GENERAL DESCRIPTIONThe OZ529 includes a high efficiency DC/DC buck converter and a high current USB power switch designed for USB port power supply applications. Withcurrent mode DC/DC conversion control and internal compensation, OZ529
provides fast line voltage transient response to minimize application component
count.
The USB power switch employs a proprietary design technique that provides
output voltage vs. load current compensation. The adaptive buck converter
output voltage control achieves a reliable, flexible and efficient solution for highcurrent USB port, power supply applications.

APPLICATIONS		• USB Port Power Supply

Patents pending.

51

APPLICATION DIAGRAMOZ531FEATURES• Current mode PWM Controller• Built-in high voltage (500V) start-up circuit• Low standby power meets Energy Star® specification• Current mode control with frequency fold back under light-load condition• Built-in synchronized slope compensation• Drive current up to 500mA• Leading-edge blanking at current sense• Protection features:- Under-voltage lockout- Clamped gate output voltage at 18V- VDD over-voltage- Cycle-by-cycle current limiting- Output over-current; short circuit; and thermal protection

GENERAL DESCRIPTIONThe OZ531 is a highly integrated current mode Pulse Width Modulation (PWM)
controller that is ideal for offline AC/DC flyback converter applications.
The controller operates at a fixed frequency of 67kHz. With a built-in highvoltage start-up circuit, OZ531 eliminates the power loss caused by start-up
resistors. The driver outputs a soft-drive signal which reduces electromagnetic
interference in the converter system.

APPLICATIONS		• Battery Charger• AC/DC Power Adapter

Patents pending.

52

APPLICATION DIAGRAMOZ531AFEATURES• Current mode PWM Controller• Built-in high voltage (500V) start-up circuit• Low standby power meets Energy Star® specification• Current mode control with frequency fold back under light-load condition• Built-in synchronized slope compensation• Leading-edge blanking at current sense• Protection features:- Under-voltage lockout- Maximum gate drive output and clamp- VDD over-voltage- Cycle-by-cycle current limiting- Output over-current; short circuit; and thermal protection

GENERAL DESCRIPTIONThe OZ531A is a highly integrated current mode Pulse Width Modulation (PWM)
controller that is ideal for offline AC/DC flyback converter applications.
The controller operates at a fixed frequency of 67kHz. With a built-in highvoltage start-up circuit, OZ531A eliminates the power loss caused by start-up
resistors. The driver outputs a soft-drive signal which reduces electromagnetic
interference in the converter system.

APPLICATIONS		• Battery Charger• AC/DC Power Adapter

Patents pending.

53

APPLICATION DIAGRAMOZ533
FEATURES• Integrates power MOSFET• Supports wide input voltage range• Up to 3A output current capability• Stable operation without output capacitor• Fixed operation frequency• 100:1 ratio PWM dimming control for LEDs
• Built-in soft start function• Over-current; LED short circuit; and thermal protection

GENERAL DESCRIPTIONThe OZ533 is a high power DC/DC buck regulator controller designed for LED
backlight and general lighting applications. It is designed to drive single or multiple LEDs in series with up to 3A output current.
OZ533 integrates a 36V VDS N-Channel MOSFET, which supports up to 5A peakcurrent. It provides fast line voltage transient response to minimize application
component count. The operating frequency is fixed at about 800kHz, whichbalances the efficiency while minimizing the sizes of the components chosen for
applications.

APPLICATIONS		• AC/DC Power Supply• PFC

Patents pending.

54

APPLICATION DIAGRAMCompany Background
Founded in April 1995, O2Micro® International Limited (NASDAQ:
OIIM) designs, develops and markets innovative power
management and e-commerce components for the Computer,
Consumer, Industrial/Automotive, and Communications markets.

O2Micro maintains an extensive portfolio of intellectual property, andhas numerous Trademark Applications and Copyright Registrations.

The company’s extensive list of customers includes many of theworld’s leading electronics manufacturers.

For additional information, including sales office locations, please
visit the O2Micro web site at www.o2micro.com.

Copyright © 2012-13 by O2Micro. All rights reserved.
PO2WER, the O2Micro logo, O2Micro, and combinations thereof are registeredtrademarks of O2Micro. Free Dimming and combinations thereof are trademarksof O2Micro.
All other trademarks are the property of their respective owners.

55

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