Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 18, 2016 by lpcware
Content originally posted in LPCWare by jrr_leon on Thu May 12 01:06:30 MST 2016

I'm getting crazy... I made a 1st proto with a LPC4357 (based on the LPC4357-evb board). And It worked ok.

After that I've made a second version with some changes not related with the MCU... and  I'm unable to even discover the JTAG devices. I've soldered and unsoldered about 6 times the MCUS in 2 diferent boards, checked all the PINS.. the JTAG (on a 10 pin connector) signals... and everything is OK (except that the MCU doesn't answer).  After that I unsoldered the MCU into the old (working) PCB board and I soldered the new one... and the new one doesn't work. Happens the same whit it.

I tried to Pull up  the 2_7 pin (and also Pull down... just in case) nothing

The external oscillator doesn't start, But I tested it on the EVB and happens the same when there is not program burned.

The MCU power consumption is about 75mA and when I reset it goes to 5mA... then I think that the MCU is working.

The only difference is the MCU manufacturing date and silkscreen code (on the 2nd and 3rd line).

It's possible to have an issue into the lot?

Thank you very much !!! I don't know that happen.