The LEDs are not damaged.
At very, very low currents, even miniscule differences in forward voltage between dies(like 0,005V) will make them light up or not in a 6V LED.
I seem to recall a couple other people having this issue. They might have had an MT09R, though. Both lights used the same exact driver (the Haikelite made Texas_Ace driver).
I unsolder the yellow wire from SWLED and tap it to prevent short, but light leakage is still there. So I will order some Vishay FET soon.
I notice there is one very short blue wire, I wonder what is the purpose, can’t recall any info about it. Anyone knows its purpose?
There were 2 switch LED’s in the factory driver, that other wire is for the other switch LED I am pretty sure.
The original MT03 and MT09R have a blue and red back lit button (battery checker), whereas the TA variant has only one colour right? Hence the redundant wire.
Thanks. That makes sense.
Haikelite really needs sharper cutter on that wire.
I finally got my FET replaced with Vishay SIRA60DP just now. The printing on the FET is very sharp compared to the FET used by Haikelite. I highly suspect Haikelite uses fake FET.
It is not leaking faint light anymore. Will continue to monitor.
That’s good to hear. I’ve been trying to study up on N channel FETs like this and man are they complicated. Hard to measure as well.
Interesting. I've been using SIRA20DP FET's but not the A60 - haven't looked at the specs. Mostly now though I use the Infineon, this one: BSC009NE2LS5ATMA1.
For the FET's for our use, the 80-100 amp capability is the standard now. You want to look at the resistance specs, like Rds, and the timing specs. I don't understand it all for sure. For this light though, you want to make sure it's at least 16V rated but also does well at 6-10V. These high powered FET's run pretty cool now - great for higher voltage LED's and high amp single or multi LED setups.
Jason, I measure SIRA60DP Rdsoff to be non measurable with my dmm. Haikelite fake SIR800 measured about 55Mohm. I think this 55Mohm means it is not completely open. Just my suspicions why it let some current through.
Ya, it is hard to understand so many choices of FET. Their specifications can be fun to read.
I focus mainly on Vishay, should have included Infineon in my search.
Did you apply power to the source and drain when you measured? I hear you need to do that in order to get a true resistance reading.
No voltage applied. I meant i measured Rdsoff, not Rdson.
Yep, just as I suspected. They did indeed use fake FET’s against my will and recommendations.
In their defense though they are apparently overflowing on china supplier shelves. Every driver I have worked on in china so far has ended up with a fake FET on the first prototype. Which is why I insist on prototypes being tested by me. HL never sent me a driver to test so I was not able to test it in person.
Now standby current is stable. It’s about 58uA blue led off and 166uA blue led on.
Are you sure Haikelite knew they were buying imitation units or maybe their supplier said they were real and then sent them fakes.
Ya, too bad HL is not investing more time and money into getting real FET. It could have saved them and their customers from troubles. Based on quantity they buy they can get quite low price per FET. I don’t understand what’s their logic.
I don’t think they knew they were fake when they ordered them but I did tell them to be on the look out and send me a sample to check which is what they didn’t do.
It was not a malicious use of fake components by any means, they just skipped out on the final step that would of prevented it.
I am not going to get into a lot of detail but lets just say there are 2 fractions in the HL upper management. 1 side is good and I support today, the other is classic china business practice that leads to issues like this.
Hey TA!
I was just reading all these recent posts with some concern. I just received last week an MT03 TA. If mine has a fake FET driver is there an easy way for me to identify that?
When you say that the fake FET’s are not suitable for extended use it makes me concerned this light will fail shortly after whatever the warranty period is given that it’s not going to be a daily use light.
I’m light years behind you guys in technical understanding and mechanical skill but I’m familiar with working with electricity. I’ve never worked on small circuitry before but don’t want my recent investment and so far favorable purchase to be for not
It seems like the majority of fake FETs are doing their job. Problem signs are if the main leds stay on or if you increase the current through the FET by adding bypasses to the springs. Too much current could make the FET fail completely.
I imagine all these factory drivers have the cheaper FETs. Yours included.
Maybe DENGOH can hold the old FET next to the new one to photo the difference.