Cree LED Flashlight hack – Disabling different modes (Sipik SK68 Clone)

Around a month ago I purchased a Sipik SK68 LED flashlight clone on eBay, for a grand total of $4.04! Shipping took around three weeks which isn’t bad considering it was free, but when I started using it there was a really annoying design flaw.

The Flashlight

It is focusable and runs on one AA 1.5V battery, or one 14500 3.7V lithium battery. The brightness with a 14500 battery is around 300 lumens which is seriously bright. An average incandescent flashlight ranges from 10-20 lumens. It’s a great deal for the price!

The housing is a little tacky, however you can’t complain for the price.


It is equipped with a toggle switch for power and features an acrylic lens for focus. When it arrived the anodised aluminium coating (the paint) was pretty scuffed already, however it’s not an issue.
Here’s an image of what you should expect with one of these running off a 14500 battery, note that the image is not mine and is from here.

The Issue

This flashlight has one very poorly engineered feature and that is its modes.
It has three modes: Bright, Dim and Strobe, but to switch modes the light has to be turned off, and back on. This is a huge inconvenience when you switch it off in the Bright mode, as on the next power cycle it will be in Dim mode. You have to cycle modes to get it back to normal again.
This frustrated me, and I had no need for the other modes anyway, only full brightness. Time to fix it!

Disassembly

The first step is disassembling the flashlight. I started by unscrewing the lens cap, revealing the Cree LED emitter and lens.

Next, the LED “pill” needs to be removed – this holds the driver and LED emitter.
The focusing ring can rotate freely, but the LED pill (the silver Aluminium part) is tight. Unscrew it by holding it to the focusing ring with pliers, and unscrew them both. The pill will unscrew, then just pull the pill out.

At the bottom of the pill there is a circuit board, with markings JX2205. I couldn’t find any valuable info about it online. Simply pop the circuit board out with a screwdriver.

The circuit board contains a boost converter – this boosts the voltage from, say, a 1.5V battery to the higher voltage needed by the LED. It also provides a constant current, which is required for all high-power LEDs.

The Fix


After visually inspecting the board, I spotted two ICs (chips) which could have been the culprits.

One was a six legged IC labelled 601, which turned out to be the boost converted driver chip. Nothing to see here.
The other one which I assumed was a transistor turned out to be our culprit. It had only 3 legs and was labelled 8133A. After a quick Google, I found this info page.
It is labelled “5W three function LED driver IC“. Perfect.

The schematic shows that it includes a transistor between pin 1 (LX) and 3 (Ground) which switches the LED on and off. All we need to do to bypass it is to connect pins 1 and 3 together.

After checking the board, the whole outer ring acts as a Ground connector, so we can simply solder on a jumper between pin 1 on the chip to the outer ground, as shown below as the arrow:

After a quick, messy soldering job, the jumper was in place:

Now all you need to do is reassemble the housing and you’ll hopefully be holding with a sweet 1-mode flashlight!
The driver in many Sipik SK68 flashlights and clones will vary from different batches/manufacturers, however if your driver uses this chip then the process should be the same. If not, just search the part numbers of the ICs until you find the culprit.

This project was a great success and makes this flashlight a great buy in my opinion. Please let me know if you try this!

Disclaimer: If you do this then it is at your own risk. If you break your flashlight I will not be held responsible. This will obviously void its warranty so be careful and good luck!

18 Thoughts on Cree LED Flashlight hack – Disabling different modes (Sipik SK68 Clone)

  1. Thanks for your article about the Cree flashlight hack. I followed your instructions and was able to do the same to my BriteStrike BD-198-HLS

    I had to modify the fix a little, so I only ran a wire from pin 3 to pin 1. I did not go all the way to the ground bus at the edge of the light unit. It works perfectly now!!

    I was thinking though…If we could fit a PBNC on that jumper, we could cycle through the modes as needed…but only when WE WANT TO!!

    Like I said, Thanks for the tutorial. I’m not good with the component level stuff, so i would’ve been lost without the help.

  2. Erm, nearly ALL flashlights operate in cycle mode, and you have to turn it off and on to cycle through. I do agree strobe should be available to turn off, but as I have bought it for my elderly neighbour (93, i didn’t want him near LI-ions and he liked my TANK 007 AAA torch, so I got him a slightly bigger AA torch).

    Even for him the strobe mode is not an inconvenience as it is so easy to change modes. Its also handy as he goes for a pipe smoke in the garden gone midnight, when our streetlights go out.

    We have always been nightowls, always up until at least 1 and always up still in time for work, but if he had a fall in his garden, he can flash strobe into out windows and we will know, so it is quie handy for US, I understand not everyone.

    1. Not really, decent designs like the convoy remember what mode you were last in for more than 5 seconds, and can even switch mode sets.

      Even my cheap supfire knock off always starts off in the same mode.

      This annoying design is simply based on poor design.

  3. Followed the instructions almost to a T. Instead of a jumper, I just flowed some solder from pin 3 connecting to the ground ring. On mine they were .5mm apart. Perfect. Thank you sooo much for your post!

    Brian

  4. I just finished making this change to a 5 mode flashlight that had a chip labelled HG5K1. Looked the same, but I couldn’t find a datasheet online for it so I gave it a try as described here anyway. Worked like a charm! I just went from pin 3 to pin 1 with a single strand from some heavier copper wire I had.

  5. I used your method on a 5 mode Skywolfeye aka Shadowhawk X800 flashlight. The 3 pin chip was labeled HH5. I could not find data on this anywhere, but soldered pin 1 to the grounding ring as you show, and now have a good quality single mode on/off flashlight! Thanks for posting this!

  6. Was about to go blind, getting flashed in the face so many times trying to figure this one out. Thank you so much for putting this up!

    Mine was smaller and also just needed to be soldered to negative. Works great now!

  7. I’ve never had a need for a flashlight that did anything else than turn on or off. Cree style bulbs have such a nice and uniform beam it’s like turning the Sun On and have it adjustable. Whenever I hear noises outside in my backyard, like someone trying to get in my work building, I want to go outside and turn the flashlight on and see what’s happening. I don’t want a strobe or anything else. Just the darn thing ON. Thank you for your hack. You made a bunch of my favorite flashlights perfect.

  8. I thought this mod was what I needed for so long. But on one of my flashlights I decided to test it. It’s a 18650 Cree flashlight. All those Cree flashlights, no matter what battery they require, uses similar circuitry to control the power and give it their “amazing modes”, yuck! The only difference between them in the circuitry is how much power the LED needs and how many modes they have. All mine are 3-modes. The untouched flashlight lasted 7+ hours with a full charge, before it got dim and it only got warm to the touch after the first half hour. I use a Panasonic 2900mah battery. After the mod I tested it and after half an hour the flashlight was too hot to hold. So I turned it off. I don’t know how long it would have lasted because I believed it would have burned it. I then reverted it to it’s original configuration… It is obviously pulling more power and is obviously not regulated… I would like a mod that only stick the flashlight in one mode, on/off, and keep the current/voltage regulated rather than giving the LED the full power of the battery without much restrictions. This kind of mod will certainly shorten the life of the flashlight. I will test my other flashlights and see how hot they get. I’d like to know if someone else tested their flashlights before and after the mod and what was their results.

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