CSD15380F3 Source-Gate Protection Diode

Dylan Owens

Other Parts Discussed in Thread: CSD15380F3, CSD23280F3, CSD23381F4

Hello,

The CSD15380F3 is shown in the datasheet as having a diode from the source to gate, presumably to protect against negative voltages at the gate. However, there's no information in the datasheet on how much current this diode can conduct, or what the working voltage is.

Does TI have any information on the characteristics of this diode?

Thanks,

Dylan

over 7 years ago

0 Brett Barr1 over 7 years ago

TI__Mastermind 18200 points

Dylan,
Let me look into what the specs of this diode are. I will get back to you tomorrow.

0 Brett Barr1 over 7 years ago in reply to Brett Barr1

TI__Mastermind 18200 points

Dylan,
I just explained to your sales contact, but basically here's what I said.

We would recommend limiting the current flowing through the diode to around 100uA, which would occur at around 0.6V drop across the diode. With up to -2V on the gate of the FET, that would mean we want a 1.4V drop across the resistor, so a 14kohm resistor should do just fine. Just to be extra conservative, our apps team suggested make it 20kOhm.

0 Mark Pieper over 6 years ago in reply to Brett Barr1

TI__Expert 4430 points

Hi Brett,
Does this same advice apply to the other FemptoFET devices, like the P-channel CSD23280F3 and CSD23381F4? I assume that if an application does not apply a reverse bias to the gate, there is no need to worry about series current limiting resistance, correct?
Thanks,
Mark

0 Brett Barr1 over 6 years ago in reply to Mark Pieper

TI__Mastermind 18200 points

Yep, same principal would apply. Only now obviously the gate to source would need to be biased in the other direction to be concerned about current through the diode.

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CSD15380F3 Source-Gate Protection Diode