Document 606-1

Miniature SMT Transformers
These miniature transformers were developed for use with
Maxim RS-232/RS-485 interface ICs, and are suitablefor gate drive and other power applications. They weredesigned to work with the MAX250, MAX251, MAX253
and MAX845 for providing power to the isolated side of
the interface, and are also specified by Linear Technology,Sipex and others for use with their chipsets.
They feature 1500 Vrms isolation between windings in aminiature surface mount package. Each transformer has
a stainless steel cover that provides an excellent surface
for automated placement.
In addition to the standard parts shown, Coilcraft can
produce custom transformers with voltage, inductanceand DCR values to meet your specific requirements. For
more information, contact Coilcraft.				 Volt-time		
DCR max (Ohms)
PartPri / sec
Inductance product2
number1
voltagemin (µH) typ (Vµsec)
pri      sec

Isolation
pri-sec(Vrms)

Q4470-CL_ 5 V to 5 V
400 (1-3)	  32 (1-3)
S5394-CL_ 5 V to 10 V
400 (1-3)	  32 (1-3)
U6982-CL_ 3.3 V to 5 V	  59 (1-3)	  22 (1-3)

0.950 (1-3)
0.950 (1-3)
0.700 (1-3)

1500 (1-4)
1500 (1-4)
1500 (1-4)

0.87
0.92
0.93

1 CT : 1.3 CT
1 CT : 1
1 CT : 2.1 CT

0.25
0.25
0.75

CCC

T6437-DL_
S5499-DL_
T6650-DL_

1.010 (1-2, 3-4) 1.955 (8-5)
0.540 (1-2, 3-4) 4.28 (8-7, 6-5)
1.015 (2-3)
8.250 (7-6)

1500 (1,3-8)
1500 (1,3-8,6)1500 (2-7)

1.88
1.59
1.25

1 CT : 1
1 CT : 5 CT
1:5

1.5
1.0
1.0

DD
D

5 V to 5V
5 V to 24 V
5 V to 24 V

1000 (1-4)
134 (1-4)
160 (1-4)	  48 (1-4)
176 (2-3)	  48 (2-3)

1. When ordering, please specify packaging code:
Q4470-CLD
Packaging: D = 13″ machine-ready reel. EIA-481 embossed plastictape (Size C: 1000 per full reel; Size D: 500 per fullreel). Quantities less than full reel available: in tape(not machine ready) or with leader and trailer ($25charge).
B = Less than full reel. In an effort to simplify our partnumbering system, Coilcraft is eliminating the needfor multiple packaging codes. When ordering, simply
change the last letter of your part number from B to D.
2. Volt-time product is for the primary.
3. Capacitance measured from full primary to full secondary at 200 kHz.
4. CT indicates center tap.
5. Calculated output power based on 150 kHz operating frequency.
Power varies depending on application.
6. Ambient temperature range: –40°C to +85°C
7. Storage temperature range: Component: –40°C to +85°C
Tape and reel packaging: –40°C to +80°C
8. Resistance to soldering heat: Three reflows at >217°C for 90 seconds(+260°C ±5°C for 20 – 40 seconds), allowing parts to cool to room
temperature between.
9. Electrical specifications at 25°C.
Refer to Doc 362 “Soldering Surface Mount Components” before soldering.

1.25 (6-4)
0.950 (6-4)
1.800 (6-4)

Pri / sec
Pri : sec
capacitance Turns
typ (pF)3
ratio4

Power5(W)Size	       			 Chipset
Linear Linear Maxim Maxim Maxim
LT1952 LTC3900 250/251 253/845 3535E
Q4470-CL		
S5394-CL				U6982-CL				T6437-DL
S5499-DL				T6650-DL				Q4470-CL
1Pri 2
3U6982-CL

615 SecPri 234

S5499-DL881Pri 32
41Sec
5US +1-847-639-6400 sales@coilcraft.com
UK +44-1236-730595 sales@coilcraft-europe.com
Taiwan +886-2-2264 3646 sales@coilcraft.com.tw
China +86-21-6218 8074 sales@coilcraft.com.cn
Singapore + 65-6484 8412 sales@coilcraft.com.sg

Pri 2
34

17Sec
6



6SecPri 2
34T6437-DL



S5394-CL

65 Sec

Sipex
Sipex
SP3222 SP3232

4T6650-DL
27SecPri

5

Document 606-1

36Revised 05/05/21© Coilcraft Inc. 2021
This product may not be used in medical or highrisk applications without prior Coilcraft approval.
Specification subject to change without notice.
Please check web site for latest information.

Document 606-2

Miniature SMT Transformers
C SizeDot above
pin 1

0.260
max
6,60

Q4470-CL, S5394-CL, U6982-CL

0.215
max
5,460.004 / 0,10

Recommended
Land Pattern

0.050
sq
1,270.275
max
6,99

0.100
2,540.100
2,54

1

6

0.023
0,60

10.283min
7,200.350
max
8,89

4

30.3759,530.039
min
1,0Bottom View
Weight 510 – 550 mg
Terminations Tin-silver over tin over nickel over phos bronze
Packaging 1000 per 13″ reel Plastic tape: 16 mm wide,0.34 mm thick, 12 mm pocket spacing, 5.33 mm pocket depth

D SizeDot above
pin 1

0.344 max
8,75S5499-DL, T6437-DL, T6650-DL

0.215
max
5,46

0.004 / 0,10

0.415
min
10,55
0.500 max
12,70

0.500
12,70
0.075
1,905
0.023
0,60

Recommended
Land Pattern
18

10.0501,27
0.100
2,540.400
max
10,160.100
2,54
450.035min
0,90

Bottom View
Weight 0.98 – 1.1 g
Terminations Tin-silver over tin over nickel over phos bronze
Tape and reel 500 per 13″ reel Plastic tape: 24 mm wide,0.36 mm thick, 16 mm pocket spacing, 6.13 mm pocket depth

US +1-847-639-6400 sales@coilcraft.com
UK +44-1236-730595 sales@coilcraft-europe.com
Taiwan +886-2-2264 3646 sales@coilcraft.com.tw
China +86-21-6218 8074 sales@coilcraft.com.cn
Singapore + 65-6484 8412 sales@coilcraft.com.sg

Document 606-2

Revised 05/05/21© Coilcraft Inc. 2021
This product may not be used in medical or highrisk applications without prior Coilcraft approval.
Specification subject to change without notice.
Please check web site for latest information.