TMP423： As a replacement for TMP421

Hi Masashi,

It is OK to connect pin3 and pin4 to GND on TMP423.

However, if you are doing a BOM swap (no layout change,) you will not have a return path for your remote junction (TMP421 pin2.) You need to make a connection to pin4, or connect both the former pin2 and TMP423 pin4 to GND.

thanks,

ren

Hello Ren,

Thank you for your reply.
My explanation was not sufficient about that

In the original circuit of TMP421, pin 1 and pin 2 are open. (Not connected)
Right now I'm only using a local temperature sensor.
Do I need to connect pin1 and pin2 of TMP423 to GND when performing BOM swap? Is it okay to open it?

Best Regards,
Masashi

If you have no remote junction in your TMP421 design, it is fine to leave these pins as-is with TMP423.

thanks,

ren