DRV8702D-Q1: Low-Side-Fet configuration (only) - possible?

Matthias Muench

Part Number: DRV8702D-Q1

Hi,

a colleague has sent me an incomplete schematic proposal.

He wants to use a DRV8702D-Q1 for driving a nfet in low-side-configuration. I have checked the datasheet superficially and I'm not sure whether it is possible. I think a gate driver fault (GDF) will occur and disable the FET.

Is there a chance to get it working or is this completely impossible?

Thx a lot,

Matthew

over 4 years ago

0 Pablo Armet over 4 years ago

TI__Mastermind 37683 points

Hi Mathew,

Can you resend the picture? I am not able to see it.

I need to look at the schematic to make sure the design can be implemented without any potential problems. In general cases, you should be able to use the DRV8702D-Q1 as a low side driver. The gate drive fault will not be triggered as long as there is no short or overcurrent condition on the MOSFET gate or the IDRIVE setting is sufficient to turn on the FET before Tdrive expires. You can read this app-note lo learn more about smart gate drive

0 Matthias Muench over 4 years ago in reply to Pablo Armet

Prodigy 30 points

Hi Pablo,

thanks for your answer and the app-note link. I've inserted a part of the schematic.

Best Regards,

Matthew

0 Pablo Armet over 4 years ago in reply to Matthias Muench

TI__Mastermind 37683 points

Hi Matthew,

Just a couple questions regarding your schematic:

Is GND_protected and GND nets connected anywhere in the rest of the circuit or are they seperated?
Which ground is connected to the GND pin of the driver?
what is the purpose of the diode? is it for reverse current protection?

0 Matthias Muench over 4 years ago in reply to Pablo Armet

Prodigy 30 points

Hi Pablo,

1. GND_protected and GND are connected in the circuit. Only difference is that protected includes a polyfuse

2.GND_proteced

3. We want to switch an inductive load (compressor).

Best Regards,

Matthias

0 Pablo Armet over 4 years ago in reply to Matthias Muench

TI__Mastermind 37683 points

Hi Matthias,

You should be able to use the DRV8702D-Q1 as a low side driver like shown in your schematic. However, you want to make sure that the voltage difference between GND_protected and GND is not too large.

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DRV8702D-Q1: Low-Side-Fet configuration (only) - possible?