odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd reading.

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

power supply voltages all correct with all boards hooked up, seems to be mainboard, trying to narrow down to component, but it no easy.

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

when the tv is on its just a snowy picture, can't see the menu, acted the same when it was screwed down, only had it on its edge to test ics on bottom.

[mmartell]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

Yes but obviously this tv isn't working so first you need to know if the power supply voltages are all there at the connector.

Also when you are holding the board on edge it isn't grounded to the chassis like it has to be as you make no mention of using a clip to ground it.

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

The input voltage may not be there until the mainboard sends pson to power supply and the power supply in turn turns on the main board. Not enough information here to go by.

tested with tv on, all boards hooked up, tested ones on bottom of board, by holding mainboard on its edge, so it wasnt screwed down.

[mmartell]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

The input voltage may not be there until the mainboard sends pson to power supply and the power supply in turn turns on the main board. Not enough information here to go by.

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

on at least one of these ics on the bottom of board, the ground on one reads 2.5 on top and the same ground at bottom starts at 22mvs goes to 200 mvs flashes ol then starts back at 22mvs does the same thing over, strange two very different readings on the exact same ground?

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

I think ic102 should have the same reading, ie, 2.5-G, 1.8-input, 3.3-output, but it reads 5.4mv-G, 13.3v-input, 7.9v-output. don't know, should the input ever be bigger than the output?, thanks.

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

not exactly sure Alistair E, but I think they regulate voltage.

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

acording to datasheet, ic101 should read 2.5v-ground, 1.8-input, 3.3-output, I'm getting 1.79-G, 4.7mv-Input, 3.34-output, looks like the input is way off?, and every dam one of these 11 ics has one reading in mv, strange.

[nomoresonys]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

sorry guys, its my samsung lcd tv mainboard, I'll grab a pic. http://www.shopjimmy.com/samsung-bn9...main-board.htm

[Alastair E]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

A Vague Clue on what the device actually is would be good!

Is this a TV, a Video-Recorder or what? --What does this board do in that device and what are the IC's supposed to do??

[tom66]

Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read

Are you talking about a Y-buffer board?

[nomoresonys]

odd IC test reading, have 8 ics on bottom and 3 on top of mainboard all give odd reading, get a volt reading on two of the pins but theres always a reading on one of the 3 pins that reads in mv, which is millivotes I guess, you think I need to maybe replace all of these, Thanks.