Hi, > So checked a bare new pcb to injet 20V at TP4 only, got no current. So > 1V2 loop on pcb is good. > Then we were suspicious the quality of coupling capacitors on 1V2 loop. > I need to use more precisely current meter to measure which capacitors > caused this? 470nF, 4.7uF or 100uF? > I'll report this results.
After used Agilent 34401A 6.5 multimeter and moved #1 pcb's decoupling capacitors(C49, C51 & C57) to a new bare pcb with 100uF/ 4.7uF / 470nF each at 1V2 TP4 trace, I injected even 20V more than 6.3V spec.; the current got is: a) 100uF >> 0.2uA b) 4.7uF >> 0.2uA c) 470nF >> 0.1uA The measured results even could be assumed having no current leakage of those capacitors because of resolution. so the increased 0.12A is indeed real dissipation by VCCINT when power-up. FYI. Adam _______________________________________________ http://lists.milkymist.org/listinfo.cgi/devel-milkymist.org IRC: #milkym...@freenode Webchat: www.milkymist.org/irc.html Wiki: www.milkymist.org/wiki
