Hi Tom, will have to catch up a little with this. Your part selections seem good though.
The 7135 seems to do OK with the inductive spike abuse in 1 S, so with the addition of C3 and C4 I would still expect them to survive in 2 S.
The long wires for sure does not help. And then there is just the sheer power (amps) in these builds.
add C3, C4. Is this right? For 2S
Steel_1024: Not my board, but from the photo C4 looks good. C3 does not.
Tom, for the lone 7135: Was wondering if the 7135 is more vulnerable when its gate is high. You might want to try keeping the 7135 off while the FET is working.
Yea, Steel's C3 did look suspect. Loooks like it goes from Batt+ to Batt+ (LED+ to LED+), but wasn't sure.
Hhmm - interesting idea for running them independently... Means a different ramping table I suppose, not sure how to do it actually. I was doing a bunch of testing with ramping at the time.
For the ramping, think I'll just take my best shot at it, then fully test it, then worry bout the smoothness later. Thanks!!
Are the A705NGT’s Mike C mentioned in post 63 in the Q8 modding thread any better than the 7135’s?
Lexel found them here. http://www.ebay.com/itm/10PCS-A705NGT-330-Encapsulation-SOT-89-/132216716613#shpCntId
I ordered those, but no clue what I ordered. I didn't even know a Q8 modding thread existed - weird.
Just read up on them in that Q8 mod thread, sounds very interesting at 12V rated - maybe it will do the trick after all. We'll see. Shippping is slowww, think still in China or on the way.
Ohh - datasheet here: http://www.datasheetlib.com/datasheet/1130180/a705_add-microtech.html
So it looks like I ordered the 330's, which are 330 mA. They do have a part # for the 350 mA version.
You and the monsters you build are the ultimate testing grounds. If they survive Mountain Electronics might consider stocking them.
Maybe they can replace the 7135’s in single cell lights as well.
Yea, I should really run them through a barrage of tests. Would be great to find a more reliable replacement. At 50 cents each, they are back to the high price though we all once paid, back when Illumn.com was about the only place you could buy them. But we'll see in higher qty. If they work out, I'll have to check for other sources.
Ohh - datasheet here: http://www.datasheetlib.com/datasheet/1130180/a705_add-microtech.html
So it looks like I ordered the 330's, which are 330 mA. They do have a part # for the 350 mA version.
Oh boy... These are as bad as the regular 7135's, maybe worse - specs are sketchy, only place I could find to buy them was on this one ebay site.
Amazing what pops up when you go trawling around with this stuff:
An 8V to 30V, 1.2A SOT-89 switching buck driver IC I’d never even heard of… complete with the usual sketchy “datasheet”:
A705x，x= 350mA
I can send you 20~30 to try, but there is no moon.
Does anyone know what the number on the second line mean on the 7135 chips. Everyone I find seems to have a different number.
I dont know what current these pass through but do have the claw on them.
Not sure what you mean by there is no moon. With Narsil/NarsilM, you can set the level of moon mode yourself in the configuration UI. Are you saying only the default level does not work?
Doesn't matter much to me if we have to bump up moon mode level by a 2-3 PWM values, but more than that is more effect, but probably ok - it all depends..
MrsDNF - yes, though are the classic good ones, but they are also the ones I've been blowing up on the 2S high amp mods. But the thing is will you get the ones as pictured?
I test A705X on MF-01 2S, 2P3S all 18 LED
I adj moon level to 7
No moon light still
Ok, then probably the PWM's speed would have to be slowed down for moon - TK and I have done this before and it works for other 7135's. Again, you are on the bleeding edge here - these things need to be tested. New parts need some R&D, and they simply may not do the job. Maybe the one A705X won't do - might need 2-3 for example, which still isn't bad, and do-able.
Are those 350 mA A705X parts available for me to buy somewhere? Only on Chinese sites?
A705X parts bought from China Tao-Bao chinese web.
I can order some for you, PM
On ebay, A705W 330mA
May be able to ask the seller, the seller should also be able to find A705X
Traditionally the second number on chips is a date or batch code. Used to be year and week of year. These days it is often a batch code or no number at all.
Last 7135s I bought were from Aliex, following reports of inconsistent product from FastTech. First set from Aliex came 40 of the ‘claw’ type and 60 with no logo, in spite of the listing photo that showed the ‘claw’ logo.
Second set came 200 all of good type. Dealer ‘STIME’. I did confirm in advance with the dealer that the product was exactly as per the listing photo. STIME’s current listing photos do not show the claw.
Difficult to beat the 7135 for size, convenience, performance, cost. Would be nice to have a mainstream alternative.
Apart from the inherent slow PWM response, I have had no issues with 7135s. I only use the claw type, and only on 1S drivers though. For Tom I did set up something on a test-bench, 2S 30Q, 2S2P 3V emitters, FET+1 driver. It worked and scoped fine, albeit with 10+ V inductive spikes at the FET drain and even higher at the power feed to the driver. C3 and C4 did bring those back to values comparable with 1S setups. This was a zener-modded driver, the LDO adds another variable to the mix. Zener-mod is no good for e-switch setups (high parasitic drain) but by nature it would clamp spikes. Would have to try an LDO setup.
DEL - not much time last night, but I re-visited the MT03, still with the blown 7135 and Hyperion FET - I noticed there was a clicking sound, very noticeable on strobes. Sounds like the FET goin ON/OFF, maybe just OFF, not sure. Distinct sound though - never heard that before, accept maybe in buck/boost drivers of old - not sure.
Thanks for the replys Tom and DEL. 
I bought all my AMCs from that shop, they seem to be good
Luckily the 400 arrived yesterday have the claw
Sorry been posting this around. But, I'm having just a little fun before researching the 7135 issue. I was getting 15K lumens or so max - pretty disappointing. so I bypassed the 4 springs in the MT03 with just 22 AWG wires. Now 4 VTC6's at 4.12V do 27K lumens! Never expected to get the peak of 9K per LED, but I guess the 4 cells, specially the VTC6's help, compared to 2 LK's in a Comvoy L6.
I still have the stock double spring on the driver, no bypass, and the little longer 20 AWG LED wires (stock were shorter 20 AWG).
Edit/Update:
I swapped the 7135, added a little heat sink even to the grnd pin, made a special verson of Narsil where modes and ramping don't overlap the 7135 and FET. Tried ramping first, and it seem to blow the 7135 immediately getting into the FET range. Maybe 16 msecs between max 7135 and a low FET value was too much in too little time?
Think I should go back to the SIR404DP and give up on the Hyperion for now... What do you think?
Ohh - major :FACEPALM: , was thinking I "only" got ~15K lumens before the spring bypass's, well, forgot I left GT buck driver test code that shortened the ramping by about 25-30% or so, and even dbl click was turbo limited. :FACEPALM: :FACEPALM:
Now, stupid me, now I have way too much amps with the bypass's on true turbo.