diode question / identify

[eradz]

Attached is a crappy pic of a bad diode on tv board which the HDMI port stopped working. The other diodes test fine for the other HDMI port. What type of diode is this? I cant see any numbers on it or anything.

Thanks
Eradz

[budm]

Re: diode question / identify

What is the make and model of this TV? Did you test it off the board yet? The picture is way out off focus to see clearly.

[eradz]

Re: diode question / identify

I have not tested it off the board but I am 99% sure its bad. I tested the other HDMI diodes and that one diode tests bad. I know its out of focus and will try to get a better pic. I will have to use a magnifying glass to see anything on it.

[selldoor]

Re: diode question / identify

If as you say you are sure its bad then you may as well take it off the board - it will have to come off whatever.
If it is paralleled on another section of the board it may be easier to read the part number
on its twin.
Is the other hdmi port working ok?

[budm]

Re: diode question / identify

I can see that it is connected in series with the diode on the left, so it can be the TVS protection diode. If we can get the make and model, then we can locate the service manual for the TV. Did the TV get hit by the surge?

[eradz]

Re: diode question / identify

I will get the make / model when I get home. The other HDMI port is working which makes me think that one diode is bad. It looks like 2 diodes per port so I test them all and the one diode that is bad, the port doesnt work. A service manual would be great! Ill post the info asap.

[eradz]

Re: diode question / identify

Vizio VX32L HDTV 10A - I will post another pic here soon.

[budm]

Re: diode question / identify

Good pictures from SJ:
http://www.shopjimmy.com/media/catal...50-top_1_1.jpg

Can you get the P/N as printed on u23, u25? I found the service manual but it does not have any diagram.
http://76.254.74.102/manuals.html

[stj]

Re: diode question / identify

if in doubt, try a LS4148

[eradz]

Re: diode question / identify

Nice pic budm. I cant read U23 and U25 because I cant find my mag glass but I will have one tomorrow. Ill post what they say on here.

[eradz]

Re: diode question / identify

stj, if I replaced it with the LS4148, there is no possible way for me to kill it? No over voltage or anything crazy before identifying the diode?

[stj]

Re: diode question / identify

if it's a normal diode and not a zener type then the 4148 is a generic fit for most.

[stj]

Re: diode question / identify

looking at the foto's again, a 4148 may be a bit small to fit on the pads - i'd have to check.

[eradz]

Re: diode question / identify

I can get a measurement if you want.

[stj]

Re: diode question / identify

the ls4148 is 3.5mm long.

[budm]

Re: diode question / identify

For temporary test you can use axial leads type to try out.

[eradz]

Re: diode question / identify

Budm, ill give that a try. I think radioshack might have some til I can order more off mouser or digikey.