Document 130 -1

Base/Gate Driver Transformers• Lower cost than toroidal equivalents• Frequency range of 10 – 250 kHz and up• Industry standard pin centers• 3750 Vrms, one minute isolation (hipot) between
primary and secondary windings; 1500 Vrms, one
minute between secondaries• UL1446 Class B (130°C) Insulation System(UL File E83628)
Coilcraft Designer’s Kit No. P404 contains samples of fourstandard driver transformers. To order, contact Coilcraft orvisit http://order.coilcraft.com to purchase on-line.		
Turns ratio ±3% (pri :sec)

SD250-1L
1:1SD250-2L
1 : 1.5

SD250-3L
1:1:1

SD250-4L
1 : 1.5 : 1.5

Primary winding
Inductance (min)1Leakage inductance (max)1
DCR
Volt-time product1.5 mH4.0 µH0.4 
375 V-µsec

1.5 mH4.0 µH0.4 375 V-µsec

1.5 mH4.0 µH0.4 375 V-µsec

1.5 mH4.0 µH0.4 375 V-µsec

Secondary winding(s)Capacitance, pri to sec (max)DCR, each section (max)

50 pF
0.75 50 pF
2.5 50 pF
0.75 50 pF
2.5 SD250-1 and 250-2

SD250-3 and 250-47Sec 1

1Pri(drive)

6105Sec 2
9Recommended
board layout
10.75
19,05

51.10
max
27,940.395
max
10,03

100.032
dia ref
0,813

97

61.10
max
27,94

10.62 ±0.015
15,75 ±0,386Weight:Termination:
Packaging:

650.950max
24,13

0.15 ±0.030
3,81 ±0,762

Sec

5

1. Measured at 1 Vrms, 15.75 kHz.
2. Operating temperature range –40°C to +85°C.
3. Electrical specifications at 25°C.

Notchindicatespin 1101Pri(drive)

0.20
5,08

79100.044
dia1,120.4010,160.80
20,32

Pins 7 and 9 are not present
on SD250-1 and SD250-2

15.6 – 16.8 g
Tin-silver over tin over copper
64 per tray

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 130-1

Revised 07/17/23© Coilcraft Inc. 2023
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 130-2

Custom Version Specifications
In addition to the standard base/gate driver transformers shown here, Coilcraft can provide custom versions to meetyour specifications.
Our two basic structures are the 0.95″ high part shown and a 1.20″ high version. Both are available with either single
or double sections.

Turns Per Layer vs Wire Size*

36

ns

34

500

2040

60

80
100 120
NP (turns)

140

160

* Applies to both double and single section bobbins.

sbbi

Dniosect28

le5

0.9bbboe
blou

b26

ng

1000

h
hig

30

tec

Si

201500ins

Wire size (AWG heavy insulation)

nsbobb
ihig

h

2000

nio

32

bo2500

biob

ns

3000

1.

E-T (Volt-microseconds)

Volt-Time vs Primary Turns*

24
22
20
18
16
14
12
10

20

50

100

Nl (turns/layer)* Applies to both 0.95 and 1.20 high bobbins.

Please use the information below to determine the performance characteristics available.

Core		0.95″ high bobbins
1.20″ high bobbins
Initial permeability
2000 µ2000 µAe (core cross-sectional area)	 0.40 cm2	 0.80 cm2
le (mean magnetic path length)4.90 cm
4.80 cmBobbinMaterial		
UL94V-0, 130°C
Number of terminals available
1010
Number of wiring sections available
1 or 2
1 or 2

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 130-2

Revised 07/17/23© Coilcraft Inc. 2023
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.