East-92 4amp 17mm driver

comfychair · October 9, 2013, 6:22pm

Jumper from BAT+ to GATE to bypass any PWM-on-high issues. If it gets brighter when you do that, the code in the MCU is the cause of the low output and no amount of swapping FETs or resistors will correct the problem.

moviles2 · October 9, 2013, 6:48pm

with Jumper from BAT+ to GATE I will bypass the diode too, and I will got 0.2-0.3v more in the gate

for bypass only the pwm if it exist I must jumper from “v in after diode” to gate

te circuit is like this but with 2 more resistors

the driver I have tested don’t have pwm in high mode but maybe others will have it :Sp

ohaya · October 10, 2013, 1:25am

Perhaps someone can clarify something:

My impression (not sure, since we haven’t identified the MCU yet) is that PDU from the MCU goes to the MOSFET GATE, i.e., the output from the MCU PWM pin controls whether/how much current the MOSFET passes.

I think that the MOSFET GATE input is an analog input, not a digital input, and that the PWM output “simulates” an analog signal/level. I guess that a specific PWM duty cycle gives an equivalent (analog) voltage to the MOSFET GATE pin, so by controlling the duty cycle, the MCU can control how much current the MOSFET passes.

Is that a correct description of how this works?

moviles2 · October 10, 2013, 5:37am

in mid and low mode it have pwm from sure you can see the flicker moving the flashlight fast.

in high mode my driver don’t appear to have pwm but others appears to have it

tivo532 · October 11, 2013, 5:51pm

The East-092 I have is similar to this.
I have traced the components and it doesn’t match the schematic from Moviles2 completely.

Components are:

R1 ~ 10K
R2 ~ 66K
R3 ~ 10K
R4 ~ 1K
D1 Not sure which diode is this. Across LED+ and LED-
MCU is most likely a PIC12F629/675 or similar
FET : UT70N03

I’ll post the schematic/trace I did later.

tivo532 · October 11, 2013, 5:48pm

tivo532 · October 11, 2013, 6:43pm

HI - no PWM (steady HI) and I’m getting 4.5A

MID - 2mS HI, 3mS LO at 200Hz, getting 1.70A

LOW - 400uS HI, 4.6mS LO at 200Hz and getting 0.22A

ohaya · October 11, 2013, 7:07pm

tivo,

Are those traces for the MOSFET GATE input, or for the emitter voltage (output from driver)?

EDIT: BTW, on the drivers that I have, when I put a meter that has freq/duty cycle, it reads 49%/51% on high. I have an old Tektronix scope that I have to try to dig out from storage, but not sure that’s working nowadays, plus I don’t know if has any probes :(…

EDIT 2: When did you get the driver you have, and from where? Was it from FT?

moviles2 · October 11, 2013, 7:36pm

my schematic is from this other old driver

the east –92 have 2 more resistors like your schematic

in your schematic r2 appears to be a diode

edit: tivo532 can you buy other east –92 and test it in high mode with your tools for know if it have pwm in high mode?

ohaya · October 11, 2013, 7:40pm

FYI, Fasttech put the driver on “Discontinued” on their website earlier this week.

moviles2 · October 11, 2013, 8:22pm

tivo532 · October 11, 2013, 8:48pm

You’re right it’s a diode but not sure why they label it as R2.

tivo532 · October 11, 2013, 8:50pm

MOSFET Gate input
April 06, 2013 Fasttech

tivo532 · October 11, 2013, 8:54pm

Not available as confirmed by Ohaya. Maybe somebody can send me a unit to test.

ohaya · October 11, 2013, 9:10pm

comfychair:

ohaya:

I re-did tests. Again, this is on the bench. Tried two different batteries, a new fully-charged PD battery and a red Sanyo from a laptop pull, also fully-charged. I got about 2.35 - 2.58 amps (emitter, clamp meter). The red Sanyo actually got the higher output numbers. So, I went back to the bench supply, but this time, wanted to see how high (current) I could go (within the limits of my supply, which is 30V and 5 amps). I was able to crank the supply up to 5 amps (according to the supply display), and the supply display said 4.5V at that point. I also measured both tailcap and emitter current using a clamp meter, and that showed about 4.91 amps emitter current. So, at least with my setup: - XM-L2 T6 on Noctigon, sitting on a copper plate with thermal grease - tailcap - EAST-092 driver - Bench supply (30V / 5 amps) I am using some ~8 inch 18AWG leads with alligator clips that I made for the tailcap switch. I am able to get almost 5 amps at the emitter current, but only at ~4.5V showing on the bench supply display. I will note that the supply is still showing “CC” (constant current) mode at that point. I can still only get my setup to change modes by unclipping one of the leads from the tailcap switch quickly. Pressing the tailcap switch makes it blink, but not switch modes…

The issue is: is it direct drive on high, or not? If output does not increase when GATE is jumpered, then you have a good as-advertised driver. If it does increase, you have one of the lesser versions which is being limited by the firmware. That can’t be answered until you compare output current as-is vs. output current with GATE connected to BAT+, I haven’t seen you mention trying that yet.

I just did the test to jumper BAT+ to GATE, and there was no change in emitter current (measured with a clamp meter) when I did that.

As a kind of confirmation, I put the driver into medium mode (~1 amp emitter current) and touched the BAT+ to GATE, and the emitter current went to same as high mode (~2 amps). I had the bench supply voltage only turned to ~3.5V when I did these tests, which is why the emitter current on high mode was somewhat low.

ohaya · October 12, 2013, 1:12am

So, I dug out my scope, and one of the probes was still connected, and it still works :):

The pic above was scoping the MOSFET GATE pin when the driver was on medium.

Anyway, since I now have the scope working, I confirmed that on my driver, there was no PWM on high mode.

ohaya · October 12, 2013, 1:13am

PM’ed you.

moderator007 · October 12, 2013, 3:54am

Got my 2 drivers today. Same as yours Ohaya, hope you don’t mind, I borrowed your pic.

.
Have not had a chance to test anything yet.

moviles2 · October 12, 2013, 7:34am

with drivers with no pwm like mine without pwm in high mode the way for get more current will be to use many mosfet in parallel

like this but with mosfets for reduce the resistance “rds” and reduce the voltage losed in the mosfet (vds)

….ohaya with imr full charged battery and thick wires in the multimeter you really don’t get more than 3 amp?

ohaya · October 12, 2013, 2:34pm

movile,

Current seems to fluctuate slightly and also change after few secs with batteries. I just tried with fully-charged Efest and PD batteries, with no switch in the circuit.

Efest (emitter current 3.31 amps):

Pana PD (emitter current 3.16 amps):

EDIT: BTW, when I was doing the above, I measured the battery side voltage on one of them (don’t remember if it was the Efest or the PD) and got 3.45V. So maybe if I had a battery that could hold voltage higher, closer to 4.2V, I’d see more current, as from testing with my bench supply, I could only get 4+ amps with voltage > 4.2V (at the battery side).