LPC Microcontrollersのトピックlpc5460x cannot work after power up

lpc5460x cannot work after power up

yanqinghe — Fri, 07 Sep 2018 08:45:39 GMT

Dear NXP:

My chip is lpc54608s512 , it's a strange phenomenon ; The MCU works normal for a lot of days, but one day, it can't works after power up , and need power up twice then it works well too; If the two power up interval too long ,it's can't works too;

Do you know what's the matter with the MCU?

Re: lpc5460x cannot work after power up

Carlos_Mendoza — Fri, 07 Sep 2018 22:01:41 GMT

Hi yanqinghe,

Are you using an evaluation board? Does the same happen if you are running a simple demo program?

You mention that if the interval between the two resets is long then it can work, right? This sounds like a capacitor in your board is still charged and the remaining voltage is preventing the MCU from powering up correctly.

Best Regards,
Carlos Mendoza
Technical Support Engineer

Re: lpc5460x cannot work after power up

yanqinghe — Mon, 10 Sep 2018 02:38:55 GMT

Dear Carlos Mendoza:

I'm not using an evaluation board, we designed the board refer to the evaluation board.

I means if the interval between the two resets is long then it can't work; It looks like a capacitor must charge and then the MCU can power up ; Another phenomenon is when the MCU can't power up , the system 3.3V was pull down to 1.6V, the MCU temperature is a little high. After power off and power up the board at once, the board works normal, the software running well too ; when the MCU is running it looks well and the temperature is right too;

Best Regards

Yan

Re: lpc5460x cannot work after power up

nikolastojkov — Thu, 27 Jun 2019 19:27:41 GMT

Dear Yan,

We are experiencing the same issue on our boards. Did you fiund out the root cause of the issue ?

Nikola

Re: lpc5460x cannot work after power up

jw145 — Sun, 30 Apr 2023 20:24:20 GMT

We have a similar issue as well, very confused why it is happening. Happens the same on 3/3 custom PCBs but not every time we power them on.