topic Re: Sabresd Fault (Power socket short) in i.MX Processors

Sabresd Fault (Power socket short)

gmcclean — Mon, 07 Apr 2014 12:22:43 GMT

My Sabresd board seems to have a short across the power connector.

Looking at the schematic the board is populated with "Option 2" PSU circuitry with support for LiPo batteries. In this design the power socket is connected via a fuse to two MAX8903C chips.

I can power the board via the battery connector (both MAX8903C chips) so I know the main circuitry is fine. The fuse is also fine but I have not been able to find the large value decoupling capacitors C507/C508

Problem is I can't see what is causing the short (nothing gets hot and no component looks damaged).

I suspect a faulty surge protector but I can't find anything relevant on the schematic.

Suggestions or thoughts as I would hate to have to shunt a lot of current through board to see what goes bang.

Re: Sabresd Fault (Power socket short)

jamesbone — Tue, 15 Apr 2014 20:55:55 GMT

Can you tell us what is your board revision? The schematic that you maybe referring maybe for a different version of the board. how you measure the short accorss the power connector? is the board not powering up?

Re: Sabresd Fault (Power socket short)

gmcclean — Wed, 16 Apr 2014 09:07:41 GMT

The board is a mcimx6q-sdp, SCH-27392 Rev B3.

There is also the marking 700-27392 Rex X8

Re: Sabresd Fault (Power socket short)

gmcclean — Wed, 16 Apr 2014 09:12:58 GMT

The board is sinking over 2amps on a current limited power supply and failing to power up via the 5V socket.

I know from past experence it normally requires just over 1amp when used with the LVDS panel via the 5V socket.

Powering via the battery connectors is fine.