Hello I am trying to use EVAL6494L for my power electronic project, but it is not working. It seems it needs a bootstrap diode and resistors. Is it correct? If so, what diodes and resistors do you recommend for NTP110N65S3HF switches?

HPour.1 · ‎2022-06-21

Cristiana SCARAMEL · ‎2022-06-23

Hello @HPour.1 and welcome to the ST Community.

The L6494L high voltage gate driver integrates the bootstrap diode.

At power on there may be no charge in bootstrap capacitor, so the driver cannot start immediately with normal operation.

The bootstrap capacitor should be charged bringing the OUT node low and so turning on the low-side MOSFET.

This procedure is necessary both when using the integrated diode and when using the external diode.

I hope that these info can be useful to you, otherwise you need to better detail your "not working".

If you feel a post has answered your question, please click "Accept as Solution"

Cristiana SCARAMEL · ‎2022-06-23

Hello @HPour.1 and welcome to the ST Community.

The L6494L high voltage gate driver integrates the bootstrap diode.

At power on there may be no charge in bootstrap capacitor, so the driver cannot start immediately with normal operation.

The bootstrap capacitor should be charged bringing the OUT node low and so turning on the low-side MOSFET.

This procedure is necessary both when using the integrated diode and when using the external diode.

I hope that these info can be useful to you, otherwise you need to better detail your "not working".

If you feel a post has answered your question, please click "Accept as Solution"