Precision Products
High Frequency Power		  
 

EFD SWITCHMODE TRANSFORMERS
This spec sheet is available in printable format.

Preferred Parts:

  • EFDSPXX and EFDSMXX are preferred parts

How to choose your model:

  • Use the “sizing factor” previously calculated and the frequency to locate a point on the chart.
  • Choose the model # whose line is above the located point.
  • Note: During the design process, the actual sizing factor may vary from the assumptions used here.

EFD Style

EFD Schematic

Precision
Model Number		 Figure
Number		  

A
MAX

B
MAX 		C
MAX 		D
DIA MAX		 E
MIN		 F
NOM		 G
NOM		 NUMBER
OF PINS
EFDSP15 1 mm 15.4 23.7 7.8 0.7 3.8 3.75 13.75 8
    in 0.606 0.933 0.307 0.028 0.15 0.148 0.541  
EFDSP20 1 mm 21.7 28.7 9.8 0.7 3.8 3.75 17.5 10
    in 0.854 1.13 0.386 0.028 0.15 0.148 0.689  

 

Precision
Model Number		 Figure
Number		  

A
MAX

B
MAX 		C
MAX 		D
DIA MAX		 E
MIN		 F
NOM		 G
NOM		 NUMBER
OF PINS
EFD15 2 mm 15.4 16.7 8 1 3.6 3.75 13.8 8
    in 0.606 0.657 0.315 0.039 0.142 0.148 0.541  
EFD20 2 mm 21.7 21.6 10 1 3.6 5 17.5 10
    in 0.854 0.85 0.394 0.039 0.142 0.197 0.689  
EFD25 2 mm 27.7 29.1 12.5 1.3 3.6 5 22.5 10
    in 1.091 1.146 0.492 0.051 0.142 0.197 0.886  
EFD30 2 mm 32.8 34.1 12.5 1.3 3.6 5 27.5 12
    in 1.201 1.343 0.492 0.051 0.142 0.197 1.083  

 

Precision
Model Number		 Figure
Number		  

A
MAX

B
MAX 		C
MAX 		D
DIA MAX		 E
MIN		 F
NOM		 G
NOM		 NUMBER
OF PINS
EFDSM10 3 mm 11.7 19.7 5.7 0.8 1.8 3 11 8
    in 0.461 0.776 0.224 0.031 0.071 0.118 0.433  
EFDSM12 3 mm 13.7 21.2 6.5 0.8 1.8 3 12.5 8
    in 0.539 0.835 0.256 0.031 0.071 0.118 0.492  
EFDSM15 3 mm 15.4 23.7 7.8 1 1.8 3.75 15 8
    in 0.606 0.933 0.307 0.039 0.071 0.148 0.591  
EFDSM20 3 mm 21.7 28.7 9.8 1 1.8 3.75 20 10
    in 0.854 1.13 0.386 0.039 0.071 0.148 0.787