lpcware

LPC2478 Reset problem

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by tonko on Thu Nov 15 00:53:43 MST 2012
I have problems with reset on LPC2478 Board.
Board start normaly almost every time, but in very rare cases LPC2478 does not start.
For example Today I try to reset it aprox. 200 times and it always start properly.
Yesterday happends few times one after another that LPC2478 didn't start.

I checked if BOOT-Loader is active, but Flash Magic didn't conect with LPC.
Quartz 12Mhz does not start in case of reset failure.
On P2[10] I have pull-up 10K to VCC.
On Reset pin I have only 10K resistor to VCC. I know that there should be also capacitor to GND, but for now I don't have it, and I want to find reason why Reset does not work properly before I will put capacitor to GND.

Is it possible that 0.1uF capacitor from Reset to GND will solve problem permanently ?
LPC2478 has Brown-out detect circuit and I think that there should be no problems if I don't have capacitor.
Or should I use reset generator chip with delayed reset (TPS3801 or similar) ?

Any suggestions appreciated



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