Yes, it will help a lot if you can explain roughly how it works.
For example while measuring current consumption, it will draw about 7mA initially. And then it settled down to 360uA to 460uA. I wonder does the MCU in sleep mode after the initial 7mA.
Ya, I am suspecting the C3 and C4 too. What if one of them gone bad and becomes let’s say for example 500k ohm and will it causes very small current to flow through the LED?
I’ve made a big mess of the picture. Lol. The dark lines are the ground areas. The red lines are the positive areas.
U4 is the little FET.
U2 is the big FET.
U1 is the MCU.
The LDO is labeled.
The 5 orange circles are some of the potential leakage points.
Leakage from the MCU or LDO has to go through R5.
You might be able to unsolder the little FET, but the big one requires hot air. You can also try removing C3 and C4. You can remove R5 to cut all power beyond it which includes the LDO and MCU.
I’m not sure if the FETs can just be measured. I assume the positive and negative sides should be open.
You might also measure the caps resistance. I gave no idea what it should be. Super high resistance of some kind.
How often is the problem of new drivers HaikeLite FET TA in new MT09R and MT03?
Are there any corrections from the manufacturer or current purchases is a risk?
Unknown. I would say they are above average for having a problem.
I would say there is a risk.
I considered buying a used MT09R for $100, but decided against it. If it’s not the driver causing an issue it might be the tail cap pins breaking off or a bad connection/short in the tail cap.
If the issues pop up they can be fixed with a new driver from Lexel or some soldering, but I just decided to pass on the light. :weary:
Finally i receive replacement driver from Haikelite yesterday. I took out problematic driver but i haven’t put new driver into light yet because i want to do comparison and repair the problematic driver, possibly with power supplied to them. Visually they are similar and no fault can be found. I also assume the replacement is good driver.
I did unsolder C3 but it didn’t help, still have very dim light leakage.
Without supplying power, I measure the big FET Rdsoff between LED- and ground, new driver is in 6.xMohm while problematic driver is in 4.xMohm range. Not sure is that and issue. Maybe i should supply power and check this Rdsoff again.
Anyone knows what is this big FET below? Wish to read its datasheet to understand more.
The SIR800DP has been around a while - Richard at MtnE has been selling them - it's a very good FET, stays cool under high amps. I thought it was pretty much in agreement the SIR404DP was superior, next step up, then is the SIRA20DP which I currently use as one of my two choices. The other is the Infineon BSC009NE2LS5ATMA. I usually use the Infineon now - great specs. I believe others have had problems with the SIRA20DP.
Thanks both of you for the info. I shall report back soon.
I wonder is SIR882DP new version of SIR800DP.(updates:looks like they are for different range)
I would take my multimeter and measure the resistance on U3 from the big pad to one of the three smaller pads. Compare the 2 drivers. I think you already did this. 4 and 6 million ohms is pretty much infinite resistance, so I don’t think that is a problem.
I think you can do the same thing for U4 measuring the pad on the left and bottom.
You sure? He used a capital M instead of a lowercase m. The miliOhms range is like a dead short.
I have a 3v 3 channel TA driver here. I tried to measure across the FET and got 1K ohm. Across ch 2 I get inconsistent readings. Across the single 7135 I got 4.5k 1k ohms. (Had to break our my new Probe Master test leads. DMM is still crap, though. Lol)
I don’t have suitable FET for it. I have only a replacement driver sent by Haikelite.
Before I install this new driver into the light, I wish to investigate how to repair the problematic driver.
Being busy at work that I can’t troubleshoot it yet.