Replacing Eprom- tools/procedures

[jstiene]

Hello.

I am going to replace an EEprom on a TV main board (Coby). I am familiar with soldering but this is a little more complicated as it is a surface mount. Is there a video or suggestions posted that describes the best way to replace the EEprom..for example..is there a preferred soldering iron.wattage.etc...tips...

any help would be greatly appreciated.
Thanks!

[selldoor]

Re: Replacing Eprom- tools/procedures

Is this the 5028 - bit of a leap from sound no back light (led) to replacing the eeprom
Is it a known problem?

[jstiene]

Re: Replacing Eprom- tools/procedures

Hello.

This is a different Coby, TFTV4025. Known problem with EEPROM causing TV not to turn back on. I have replaced EEPROM's before but struggle to do it effectively. I was hoping to get some pointers from the experts out there.

[MisterD]

Re: Replacing Eprom- tools/procedures

First took note of the direction the EEPROM facing, then I took a utility knife blade and very carefully scored the legs on the EEPROM lightly over and over until I cut through them, easily removed EEPROM chip out of the way, removed each leg one at a time using a 25 watt pencil soldering iron being very careful not to lift a trace.
Placed new EEPROM in place, being careful not to overheat using flux soldered one leg to hold it in place, then finished by soldering remaining legs, tv powered on normally.

[mmartell]

Re: Replacing Eprom- tools/procedures

Hot air.

[steves7839]

Re: Replacing Eprom- tools/procedures

I was just given a "broken" Coby TFTV4025. Symptoms are no power indicator light and no power on.
I've done voltage and resistance checks on the PSB and Main board. All DC comes on stable as soon as I plug in AC. 5V, 5STBY, 24V, V+ 24 to Inverter, CE1 200V cap reads 350VDC across leads. No visible damage/bad caps.

PSON reads steady 3.0VDC at PSB and Main BD. Power ON/OFF button seems to have no effect at the Main BD ON/OFF pin.

Is my symptom the same one for which a replacement eeprom is indicated?

I know this is last year's thread but will give it a try for a few days.

[tibimakai]

Re: Replacing Eprom- tools/procedures

https://www.youtube.com/watch?v=7kyaz4Zrd78

[johnboy1313]

Re: Replacing Eprom- tools/procedures

You don't need chip quik. Just flood all of the pins one each side with one big blob of solder. Then move your iron tip back and forth from side to side quickly to keep each blob molten. The chip will lift right off, assuming it hasn't got a pad on the bottom. Then use a solder sucker and some wick to get rid of the excess solder.

[tibimakai]

Re: Replacing Eprom- tools/procedures

For who is not that experienced, that kit is safer.

[johnboy1313]

Re: Replacing Eprom- tools/procedures

I wasn't experienced at first. I found this to be pretty easy. The kit costs money and then you have to wait for it to show up.

[zomi]

Re: Replacing Eprom- tools/procedures

Kaptop tape the surrounding area
Give it 360 - 380 C of heat and it should come off nice and easy.
Best way to be honest.

[zomi]

Re: Replacing Eprom- tools/procedures

The quick solder if ok, but will not help if the centre of the chip is also soldered down.

Another method is grind the chip off then desolder the remaining legs.

all 3 methods have thier uses