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2017-01-16

Panasonic TX-P50GT30 - 7 blinks - TNPA 5335 y-sustain - FGD4536TM used instead of 30F131, RJP30H2A

I love my GT30 and when I found another one on eBay I grabbed it. It had the same 7 blink disease. See my earlier blog post about all the details.

Due to my disappointing attempt (see this blog post) to get some genuine IGBT transistors (30F131, RJP30H2A) from China, I settled with the FGD4536TM instead, which was mentioned in various blog posts in the Badcaps forum.

I got the FGD from DigiKey. They are already discontinued and not on stock at Mouser anymore. It is a good idea to order a large batch. As plasma TVs are not manufactured anymore, this type of device becomes obsolete.


As you can see, the FGD are much smaller. The RF1501 in the center also came from Aliexpress and it is genuine and working ok. The DAF30A on the far right came from a scrap board.

I also ordered a STTH20R04G-TR diode from DigiKey, which might replace the difficult to get and fake-prone DAF30A someday.

I also tried something new to resolve the loose screws problem. I observed that the screws, which have an extra bracket were perfectly solid when I unscrewed them. Why? Because they had no solder under them which floats under pressure. So I cleaned the critical one next to the DAF30 diode and some others, too.



The most popular suggestion is to use spring washers. I did that too in my previous repairs, but I think the remedy is simpler. The thing with the washers is that you need longer screws, which must not be too long to avoid drilling them into the panel.

Currently the device is running its burn-in. The FGD IGBTs have settled at around 48°C at 22° room temperature and open back cover. This is roughly the same temperature as the three 30F131, which are left on the board. Some say that the FGD run cooler. I cannot confirm this.

I'll also watch the screws. I left some with solder on the holes to have a comparison to the cleaned ones.

3 comments:

  1. The link to AliExpress FGDs was live on 16/01/18 but now points at a different chip, and no sign of FGD searching their store :-(

    ReplyDelete
  2. Thanks for pointing this out. That's unfortunate. I don't know if any of the other sellers on Ali sells legit FGDs. Digikey is sold out :-/

    ReplyDelete
  3. Well; I bought a batch of 50 for ~$12 from this source on Ali:
    https://www.aliexpress.com/item/50-PCS-LOT-FGD4536-LCD-plasma-tube-is-commonly-used-TO-252/32669824142.html?spm=a2g0s.9042311.0.0.HfzHia
    They are marked with the Fairchild F but I very much doubt they are original.
    However, they do switch cleanly at around 3.6v unlike my last failures (~1.5v), so if and when I get another SC board to try them on, we'll see.

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