CX-422 PCB Driver Configuration?

Flashlight Modding and DIY Parts
1

Howdy!

I want to thank you all for giving me the knowledge and courage to get deep into this wonderful hobby!

Now I’ve wandered off the path & seem lost.

Is there anyone who knows about the CX series of LED torch drivers?

Specifically, I have a “JawsLight” (aka “Sharks-A-Fire”) which I only ordered as a whim. Turns out to be a half-decent host, but there’s that driver… YMMV, but mine is configured for the standard “5-mode” blinkies. I went to upgrade the XR-E to an XM-L so I could use this at work, and while I’m at it, I’d really like to both uprate the ILED and delete the blinkies if possible. Deleting mode memory would also be nice, esp. if it starts in High.

Here’s a picture of the whole mess, with annotations as appropriate:

I’ve tried every way I can think of to find the source of this board, to no avail. Here’s hoping someone on BLF has been more successful!

It’s not a bad board, AFAICT, although it’s been discombobulated so long I can’t remember the mode memory…

I’ve just ordered a 60° and a 10° 21mm optic, to test for the optimum beam for work. This could be interesting, but I’d rather not orphan yet another driver (for a 105C, natch) just because the manufacturer couldn’t be bothered to write up a Datasheet (or let me do it for free just to have the info!!!) on the CX-422PCB driver.

Thank you for reading this far, and THANK YOU for any information you can share about the CX-422 PCB driver!

Dim

2

I found some data on the CX2807, which is available here.

http://www.ic-cn.cn/index.php?homepage=nhchengxindz&file=sell&itemid=273542

It seems to be a chip made to control a LED, either on its own or through activating a mosfet. In this circuit it is being used to activate a transistor, the A1SHB (more on this chip later).

That page does list a few details on how to configure modes on the CX2807.

OPT1 feet dangling, OPT2 feet dangling: In order to model a

OPT1 feet to VDD, OPT2 feet dangling: as a model two

OPT1 feet dangling, OPT2 pin connected to VDD: to mode three

OPT1 feet to VDD, OPT2 pin connected to VDD: as a model four

However it does not supply any information on what modes 1-4 are. If you give me a clearer photo of the driver (pins 1 and 2 of the CX2807 are obscured by the wire) I could try to tell you what mode it is set to and directions on how to set it to other modes.

The A1SHB is a transistor that is rated 2.8 amps continuous drain current, so it should be able to handle a XM-L.

As for the resistors, I cannot say definitively without being able to see the traces in this circuit, but I would guess (very rough guess) that paralleling some more resistors there might increase the current. (It might also be used for configuring modes, but again I cannot say without viewing the traces on the PCB)

3

I don’t have enough light to shine through this mask, to observe Traces!

It seems what I thought were config jumper pads are actually for the “LED#” legs, 5-8. LED2 (pin 6) is connected by a 2R2 to…

As far as my Fluke 77 can detect (with my fumbly old fingers), the top pads are bussed to the Gate of the A1SHB. Source of the A1SHB is on the Via for B+. I’m not exactly sure what that 103R between Gate & Source is for. I’m guessing there’s supposed to be a different program for each LED# pin…? So they’re back to being config jumpers?

I’m guessing the 2R2 on Pin6 brings the “LED2” program to the Gate of the A1SHB, which Sources B+ through the Ilim set to LED+. I’m guessing the other “LED#” pins would bring different programs, so they’d have to be mutually exclusive. I’m a long way from being able to test that.

The Drain of the A1SHB rings into the top of the bank of parallel 2R2’s which buss to the Red Wire (LED+). Net R should be 0.5R, measures 0.7R. So it’s down to Ilim after all! ??

Opt1 and Opt2 don’t seem to ring anywhere. The page you referenced (after Google Translating) suggests Opt# pins are either “feet dangling” 8) or = to VDD. I get no tone, on either OPT#, to VDD (Pin 4).

I fixed the close-up in the OP, with wires moved and lines for the Paths I think I’ve found. I noticed the A1SHB Drain is very close to the Ground ring, so I had to be very careful with it. Please don’t assume I’m right about it until I can prove it.

4

Hi, Scaru, et al.

I just stumbled across a Chinese site with more details.

Skip to the relevant part, after Google Translate and putting in linefeeds to make it readable, apparently the “engineer” who designs these things cannot make one without blinky modes!!

Sheesh! Why do I put myself through it? I don’t even want to know what/how/why the “421*” means (obviously configurations, but who freeking cares!)

Now I understand why the manufacturer refuses to provide documentation!

The trick with the FET is mildly interesting, even with the gigantic snubbing Resistor. Spreading the LED load over 4 Ilim resistors is interesting too, except that makes it harder to uprate ILED. I may crush that 10k and live with the alleged ringing, just to see if that makes it brighter (if it speeds up the PWM, bonus) …

My only question which might lead to saving this annoying card from the scrap bin would be if I could kill Mode Memory, since it seems to be configured for 421C and seems to use Next-mode-memory.

(I screwed up the text overlays on the first picture I posted. Sorry. Fixed it.)

I think the brown cap beside Pin8 of the CX2807 is the Mode Memory power buffer. I think I should short across it, or install some resistor there, to stop Mode Memory.

Anyone concur?

I apologize if I got anyone excited about this disposable driver! I had hoped it could be useful, or at least not-annoying …

Thanks for reading!

Dim