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.
-
-
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?Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search. -
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??TELEFIX
How PLASMA SCREENS WORK, X-SUS and Y-SUS what they do--
http://www.irf.com/technical-info/appnotes/an-1088.pdf
PLEASE DO NOT EMAIL ME PRIVATELY FOR REPAIR ADVICE. QUESTIONS BELONG ON THE FORUM!Comment
-
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.htmLast edited by nomoresonys; 02-06-2015, 01:12 PM.Comment
-
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.Last edited by nomoresonys; 02-06-2015, 01:19 PM.Comment
-
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.Comment
-
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.Comment
-
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?Last edited by nomoresonys; 02-06-2015, 01:37 PM.Comment
-
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.Comment
-
-
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.Comment
-
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.Comment
-
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.Last edited by nomoresonys; 02-07-2015, 06:27 AM.Comment
-
Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read
Search "how to test a voltage regulator" and post the info back as per instructions. Assuming of course these are voltage regulators you are talking about.Comment
-
Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read
So you are getting a input signal, but no menu or any OSD? Is it a lightning strike special?Comment
-
Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read
not sure CapLeaker, no background on it, the menu may be there, the snow changes slightly when I toggle thru source, but the snow is too dense to make out anything, so I can't tell if theres a menu.Comment
-
Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read
oh crap, I forgot to throw up a pic, MY BAD.Comment
-
Re: odd IC test reading, have 8 ics on bottom and 3 on top of board all give odd read
the ics I'm looking at are ic101, ic102, ic1702, and 7 or 8 more on the bottom. http://www.shopjimmy.com/samsung-bn9...main-board.htmComment
-
Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
Assuming... -
Problem
This is an LG edge LED lit LCD Display. The LEDs are on the bottom edge of the display. There are 2 bars (left and right) Each bar has many LEDs and a 6 pin connector. Each pin drive several LEDs thus is the highest current flow / heat junction. The weak lead free solder gradually fails with thermal expansion/contraction cycling and increases resistance. PSU will compensate up to a point, then when the current is too high, PSU just shut down the backlight causing a dark display. I have even seen one which the connector just fell off as solder points became completely detached.... -
This is my first attempt at troubleshooting a board like this, I know I could just buy a new board but I'm curious to figure out how this works. I've been testing different components in the evenings this week and I think the problem is with the IC failing to start up for some reason. When the board is plugged in there is no standby voltage.
Then today it randomly sprung to life like a zombie but shortly died thereafter. I have no idea why it would have done that and its the first time I've seen it running. I discharged capacitors on the board last night, then it was sitting today.... -
Hi, this is my personal laptop, which the original board (lets call it Board A) blew up PU8700 (TPS51486), making a hole on the board, i had left the laptop at my desk one day with the battery fully charged and didn't touch it for a week, but when i tried to turn it on it didn't
Thought the battery was dead, so i plugged in the charger then tried to power on, the power LED blinked once, charged LED still orange, unplugged the charger, plugged in again and I noticed the "magic smoke" smell, so i unplugged the charger, removed the back cover and saw the blown IC (the "magic... -
I have a 2DS that I am working on that has a problem reading SD cards. It knows that card is in the slot (which, means the detect pin is working anyway) but it says it can’t read the card.
Here is what I have done so far:
-Tried SD card in another 2DS and on PC, works great.
-Tried piggybacking another SD card slot (just so I didn’t have to take the other one off), same issue.
-Compared voltage drop readings from a working 2DS to the faulty one. All reads are very close except one, the 7th pin from the left, with the pins closest to you, which I believe...
Comment