CSD23381F4: MOSFET Source Low voltage output

Lan Wei Wen

Prodigy 10 points

Part Number: CSD23381F4
Other Parts Discussed in Thread: CSD23382F4

Hello,

I have some problems when using P-MOSFET CSD23381F4 as a switch.

I driving the gate with 2.8v~4.2V, and provide source voltage 0V(DC3VB power off), Drain voltage 0V .

At that time source output voltage is 0.56V not 0V (Q9- pin2 in the figure below).

=>So, please help to confirm whether the 0.56V(Vs) voltage comes from gate protection diode ?

Under the same application conditions, is there any other TI P-MOSFET whose source output is 0V.

Thanks.

over 2 years ago

+1 John Wallace1 over 2 years ago

TI__Mastermind 29525 points

Hello Lan Wei,

Thanks for your interest in TI FETs. The CSD23381F4 includes a single-ended gate ESD diode from gate to source. When the gate is driven higher to a higher voltage than the source voltage, the diode will become forward biased and conduct. I would recommend an alternative part, CSD23382F4 which includes a back-to-back gate ESD structure that will not conduct when the gate voltage is higher than the source voltage. Please note, the back-to-back ESD structure has higher leakage current than the single-ended ESD diode.

Learn more about ESD protection in TI FETs here: https://e2e.ti.com/blogs_/b/powerhouse/archive/2020/06/22/what-type-of-esd-protection-does-your-mosfet-include

Best Regards,

John Wallace

TI FET Applications

0 Lan Wei Wen over 2 years ago in reply to John Wallace1

Prodigy 10 points

Hello John Wallace,

Thanks.

Wei Wen, Lan

Power management

Power management forum

CSD23381F4: MOSFET Source Low voltage output