PCF2131TFY Battery Draw

[chadl]

A product using the PCF2131TFY is having intermittent issue where some boards are depleting their batteries in a matter of days. The batteries installed are CR2032. Are there any considerations to take or look into for diagnosing this issue? Or are there known issues with this part?

[guoweisun]

Hi

Can you share your schematic here?

[chadl]

I sent you a private message.

[guoweisun]

For some unused pins please follow below suggestions setting:

Customer can leave CLKOUT and TS1-4 pins open when not using them in application.

Customer can set CLKOUT pin to be in high-Z mode by setting CLKOUT_ctl register (13h) bit[2:0] = 111b. And set TS1-4 pin are to be inactive pins by setting Control_4 register (03h) bit [7:4] = 0000b and Control_5 register (04h) but [7:4] = 0000b.

[chadl · Accepted solution]

Turns out the issue is that there was some excess and uncleaned solder flux on all of the PCBs that was causing some excess current draw and the battery drain.