DV9500 blue LED ring of death ?

[bianchi77]

Re: DV9500 blue LED ring of death ?

Where s Pd21 and 22 I can't see the label

[BlueMidnight]

Re: DV9500 blue LED ring of death ?

There isn't really any good substitute for a proper bench power supply. Maybe if you had a 150mA fuse or something like that.

I'm not sure where those components are. But it will be written on the board somewhere. Sometimes it takes a few minutes of reading labels until you find it. But if you can find any of the components in that circuit, maybe you can follow the traces to the other ones.

[bianchi77]

Re: DV9500 blue LED ring of death ?

I followed the closest from pq62 won't be far..same like I draw pcb

[bianchi77]

Re: DV9500 blue LED ring of death ?

I have some fuses but I need to modify the connector

[bianchi77]

Re: DV9500 blue LED ring of death ?

photos
The left diodes, I reckon : PD20

The right diodes are PD21 and PD22....they're open from diode test...
I can't find their datasheet yet...

so not sure with the pin out yet...

PD20 is ok with diode test, 0.267V and 0.5V

[bianchi77]

Re: DV9500 blue LED ring of death ?

that's TL311, please correct me if I'm wrong , there are two the other one with label PU7

[BlueMidnight]

Re: DV9500 blue LED ring of death ?

Both pictures are the same. They are a little too blurry anyway. But PD20 should have 3 pins. PD20 and PD21 should have 2 pins. Make sure you found the right ones. They definitely shouldn't be open circuit in both directions. Try searching for the part numbers on aliexpress and see if the pictures look like yours.

I can't find the SW1010C datasheet either. But I found a cross reference match for 1N4148WS at Mouser. Looks like a pretty normal diode.

Yes, TL331 has "T1IG" written on the package, so that is correct.

[bianchi77]

Re: DV9500 blue LED ring of death ?

could it be that one ? it's the closest to TL331, but it's only one, the other one is not fitted

[bianchi77]

Re: DV9500 blue LED ring of death ?

will it run with 12V supply for a test ? or must be 19V ?

[bianchi77]

Re: DV9500 blue LED ring of death ?

can I subtitute PD16 with this :
https://cdn.badcaps-static.com/pdfs/...f28f191a89.pdf ?
but I don't have transistor anyway to check, must wait...

[BlueMidnight]

Re: DV9500 blue LED ring of death ?

Yeah, that might be PD22. If it's connected to the TL331 then there's nothing else it could be. And PD21 has an orange box around it in the schematic. I'm not sure what that means but maybe it means some/all boards don't have it.

It does need to be powered by the full 19V. Unless you are just checking for a short. But a multimeter in diode mode should work for that.

That's not a good substitution. The characteristics are good, but it is physically twice as big.

[bianchi77]

Re: DV9500 blue LED ring of death ?

D u Hv tl311 datasheet?

[BlueMidnight]

Re: DV9500 blue LED ring of death ?

Datasheet is here.

[bianchi77]

Re: DV9500 blue LED ring of death ?

Pin 5 to cathode of the diode

[bianchi77]

Re: DV9500 blue LED ring of death ?

I suspect the culprit is PQ62...car bulb in series can become a current limiter..?

[BlueMidnight]

Re: DV9500 blue LED ring of death ?

Max continuous current for the PQ62 is 150mA. And for PD16 it's 100mA. A bulb will draw a lot more than that unless you have many of them in series. But then you are reducing the voltage also.

So using a resistive load is okay if you are just looking for a short and maybe want to feel where it gets hot. But it's not okay if you want to power up the circuit at the correct voltage except with extra safety. A fuse is better for that.

[bianchi77]

Re: DV9500 blue LED ring of death ?

I have 500mA fuse...is that ok ?

[bianchi77]

Re: DV9500 blue LED ring of death ?

I reckon PD16 burn because of PQ62 short...do you ?

[BlueMidnight]

Re: DV9500 blue LED ring of death ?

Yes, the path to ground was through PD16 and PQ62. Hopefully a bad PQ62 was the root cause.

A 500mA fuse is too high. 150mA or less is needed. You could test with the 500mA if you test without the diode and transistors. But that's not very useful. An oscilloscope is needed to test TL331 properly.

[bianchi77]

Re: DV9500 blue LED ring of death ?

I don't have 500mA Fuse and I need to wait for the part coming...