LPC802 external reset pin not pull-up when restating

[join_ren]

We are in the debugging LPC802.  
There is a probability that the reset pin will not pull up when restarting.

Please tell me how to solve it. Thanks.

Reset Pin SCH: 

LPC802 SCH

Power & Reset 

[jeremyzhou]

Hi ,

Thank you for your interest in NXP Semiconductor products and
for the opportunity to serve you.
After having a brief review of the schematic, I don't find anything wrong with it, so I'd like to know what the ratio of boards encounters this phenomenon, I suspect that the phenomenon may be related to PCB manufacturing or soldering technique.

Have a great day,
TIC

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[join_ren]

Hi Jeremyzhou:

Thanks for your support.

"There is a probability that the reset pin will not pull up when restarting."   

Actual testing : 

1、This is abnormal LPC802's PCB can be restarting on the computer.     Use 3.3v start-up time 2ms.

2、This is abnormal LPC802's PCB cann't be restarting on the customer device.   Use 3.3v start-up time 8ms.

Could you tell me special requirement for LPC802 start-up ? 

On the computer start up:

On the customer device start up:

[jeremyzhou]

Hi ，

Thanks for your reply.
Regarding the phenomenon, you should check the hardware design, especially the power supply, external crystal, reset pin, they're essential components of the minimum system.

Have a great day,
TIC

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Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!

- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
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