IWR6843ISK: The resistors connected to SOP terminal

Hello there,

The device SOP pins cannot be at floating state as well as be directly connected to power lines for they are pinmuxed with several signals. That is why a PUPD network (with default pull down) has been deployed.

Now let's consider two conditions where the switch turns any of the SOP signals to 1) Logic low (GND) and 2) Logic High (VIOIN)

1) If the switch turns the signal to logic low (GND), 7.87k and 82.5k comes in parallel, which in series with 10k gives a strong pull down of ~17kOhms.

2) If the switch turns the signal to logic high, as per standard pull up, the voltage divider gives a ~1:10 ratio and (with no effect of the series 10k) SOP signal goes to logic high. 

I hope that solves your query.

Thanks

Swarnendu

Hi, Swarnendu,

Thank you for your reply. I understand the purpose, but why is a series 10kohm necessary?
Is 7.18kohm(7.87kohm // 82.5kohm) insufficient, and is 17kohm necessary?

Regards,
Kei

Hi, Swarnendu,

Thank you for your explanation. I understand.

Regards,
Kei

You are welcome!