topic PCAL9722 in Other NXP Products

PCAL9722

晨晨AO — Fri, 21 Feb 2025 10:21:50 GMT

问题1：IO拓展芯片PCAL9722的P1_7引脚设置为上拉输入读取不到正确电平，默认读取到为1高电平，但是当我给低电平时，读取到的依然是1高电平（通过万用表测量该引脚确为低电平）；
问题2：当设置P0_6、P0_7、P1_4为上拉输入时，P0_6、P0_7分别给低电平，读取到的值正确为0；当P1_4给输入低电平时，读取到的P1_4依旧是高电平1，并且P0_6、P0_7同时变为为低电平0（此时用万用表测量P0_6、P0_7为5V高电平）；

Re: PCAL9722

JozefKozon — Fri, 21 Feb 2025 12:35:47 GMT

Dear 超陈,

please share a code where you are reading the input registers. Does this issue happen only on one PCAL9722, or have you tested more PCAL9722 pieces? Are all of them showing the same issue?

Please confirm a source of the PCAL9722 components. Have you purchased them from one of our authorized distributors? Please see this link for a list of our authorized distributors.

With Best Regards,

Jozef

Re: PCAL9722

晨晨AO — Mon, 24 Feb 2025 01:07:28 GMT

使用的是同一程序，一共3个PCAL9722，通过SPI片选选择

Re: PCAL9722

JozefKozon — Mon, 24 Feb 2025 07:14:58 GMT

Dear Chao Chen ,

The same program is used, a total of 3 PCAL9722, selected through SPI chip select.

[A] Thank you for your answer. How many of the tested PCAL9722 are working correctly? From how many PCAL9722 working correctly are the 3 PCAL9722 faulty?

Please also answer following.

Please share a code where you are reading the input registers.

Please confirm a source of the PCAL9722 components. Have you purchased them from one of our authorized distributors? Please see this link for a list of our authorized distributors.

With Best Regards,

Joseph