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Gate drive transformers dont exist?

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treez

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Gate drive transformer does not state max leakage inductance

Hello,

Do you know why this gate drive transformer family (HM42) states the minimum leakage inductance instead of the maximum?......as you know, the minimum figure is not useful....customers need the maximum, so as to calculate the delay in turning on the FET...

https://www.farnell.com/datasheets/...65.1106301863.1511695680-287702491.1506211291

If you are also stumped, then please may you tell of a different family of OTS FET pulse transformer drivers?, which do state max leakage...F(sw) is 100khz so we need low leakage.
 

Re: Gate drive transformer does not state max leakage inductance

Probably a typo. Request a corrected datasheet from ttelectronics.com
 
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Re: Gate drive transformer does not state max leakage inductance

What's the exact part number. Arrow.com datasheet sheet shows max leakage on 20002lftr.
 
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Hello,
We are seeking an offtheshelf gate drive transformer for our 100khz, 30w Buck converter (400V to 270V).
We need it to be……………….
1:1
LPRI = anywhere from 600uH to 2mH
Leakage inductance = <1uH
V.us = at least 50
At least 1500v pri/sec isolation

We have searched high and low…would you believe no such thing exists!..or may you contrarily tell the tale of deliverance?
 

K>0.999 with 1500V isolation is not a reasonable spec.
 
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Have you looked at the Pulse Electronics
PA2000 series. Would something like the
PA2007nl meet your requirements.
 
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K>0.999 with 1500V isolation is not a reasonable spec.

Thanks, i agree that a k factor 0f 0.999 sounds high when insulation is 1.5kv....but the following part (78601/9C), from Murata , purports to have a k factor >0.999, and with an insulation of 1kv, which isn’t that far off....

https://www.farnell.com/datasheets/...MIi7mdwr_S1wIVDGcbCh1GwAuFEAAYAiAAEgLnU_D_BwE

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Thanks,
The EP5..........
https://katalog.we-online.de/pbs/datasheet/760301106.pdf
..is the best that is available, but it has a max V.us of just 30.....this is too low, i mean, our max duty cycle at our 100khz switching frequency is 0.2, and the gate drive voltage is 12V, so we would normally be ok with 30V.us, but for those times when eg the led load is not attached, and the error amplifier therefore rails high, then it will be on max duty cycle, and if the led load is suddenly re-applied, then the gate drive transformer will saturate.

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I must admit the 786 series of Pulse transformers look ok but the V.us column is said to be the “minimum” V.us product...surely it should be the maximum?

786 Series Pulse transformers:
https://www.murata-ps.com/data/magnetics/kmp_786.pdf
 

I must admit the 786 series of Pulse transformers look ok but the V.us column is said to be the “minimum” V.us product...surely it should be the maximum?
The manufacturer knows when its product is going to saturate, so he is telling you that its minimum volt-second product is that value. It can be higher in reality, but you must select the gate-drive-xformer which has the minimum above the maximum volt-second product in your application.

I understand the way you were thinking. You were thinking that the manufacturer is giving you the volt-second product you can apply... but not, he is concerned about his saturation limit.
 
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