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Gate drive transformers for SMPS are a thing of the past?

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cupoftea

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Are the attached type of pulse transformer gate drives a thing of the past?? (LTspice sim and jpeg scm attached)

In the age of gate drive chips like 1EDI20N, maybe the traditional gate drive transformer has had its day?
I have layed out the attached mainly because of its cheapness….i don’t particularly like the fact that when both drivers are off, as in shutdown, the FET is not “driven” OFF…but just relys on the ~3k3 gate pull down resistor to keep it off.
Also, it draws quite significant "bias" current.

1EDI20N datasheet:
 

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  • LLC with chosen gate drive transformer.zip
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The 2N3906 transistor is the "off" driver. When there is no AC from the transformer, It will conduct when the gate voltage is above 0.7V
The 3k3 resistor is not involved in the "off" state. The path from the base of 2N3906 to "local ground" is via the transformer winding (and the 510R + 2R resistors).
 
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