Pink Atom Module

[debe]

I have used the same type of component tester. Test of 2SD1071 ST901T BU931T all darlington type ignition transistors that work in the circuit.

 

[Skelle]

Your measures shown makes it even more evident, that the HFe are not that major, but that the Uf seems highly important. Can someone explain that for a 'dummy' how that would be possible...KISS?
I'm lost when paddling through the datasheets

 

[Skelle]

Debe, do you remember from where you purchased the 2SD1071 you are testing above? Also the BU931 returns high results......where to order?

 

[debe]

Since it was several years ago & they were from Ebay, i cant remember. I did buy about 40 of them from a couple of Chinese sites. Coped 10 faulty ones from one supplier.

 

[Skelle]

For sure crappy quality..... I think i tested 50, and only a few seemed 'Ok'.....but not at all with HFe above 21-22.

 

[KeepItSimpleStupid]

Your measures shown makes it even more evident, that the HFe are not that major, but that the Uf seems highly important. Can someone explain that for a 'dummy' how that would be possible...KISS?
I'm lost when paddling through the datasheets

It's odd that 689 mV would be a darlington.

I think Uf gives an idea of junction quality, but with darligtons you have 2 in series. What if one is 0.3 and the other 0.3? Then you can't tell of 0.6 is good or not.

But Hfe is very dependent on Ic based on the graphs. Thus putting a circuit together with 2 resistors to test at a higher Ic might be beneficial. Just divide Ic/Ib for Hfe.

 

[Skelle]

It's odd that 689 mV would be a darlington.

I think Uf gives an idea of junction quality, but with darligtons you have 2 in series. What if one is 0.3 and the other 0.3? Then you can't tell of 0.6 is good or not.

But Hfe is very dependent on Ic based on the graphs. Thus putting a circuit together with 2 resistors to test at a higher Ic might be beneficial. Just divide Ic/Ib for Hfe.

The one with 17 in hfe and 1,01 in uf are one from me, else being Debe. Basically it’s watch the tester are doing, and some add a test frequence, sinus curve.

 

[Skelle]

Debe.... Any idea what surface mount TVS diode that could replace the 1N6303A.
1N6303A is pretty big, and not easy to fit onto a tiny PCB.
Think i now have like 100 borrowed darlingtons here that i'm going to test. Found some connectors that will work as sockets, which will make it far easier doing live tests.

 

[debe]

Google 200v surface mount TVS, RS component apear to have them.

 

[Skelle]

Do you think that SMBJ15A would work ok? Not sure why unidirectional....could it be bidirectional?

 

[Skelle]

Just found out that '15' means 15volt. So guess SMBJ200A would work?