LPC824 Power question

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by lavanyasubbu on Wed Jun 17 08:10:43 MST 2015
Team I am using LPC824 to connect to an external GPS GPRS module. We are seeing a strange occurrence. Need you help please.

Our logic is as follows on LPC824

1) Wait for 5 seconds (Give the whole system time to settle on power up)
2) Pull the power key of the GPS GPRS module using a GPIO pin (p0_27)
3) Wait for 5 seconds.
4) Go through process of setup initialize and loop

Problem: When in step #1 I power cycle for a short enough duration (say about 500mS) LPC824 just hangs. It neither restarts nor does it continue with the processing. On our hardware (since its automotive) our capacitance is about 470uF to stop fluctuations. I am not sure if thats causing a problem

Please note that i have a 4.7kOhm resistor between the GPIO line and the GPS/GPRS's pwrKey

Appreciate your help

Best Regards
Surendar S