Hi-Powered LED: Bypassing the 5-Way Switch

[Kingfish]

Problem: My Crees are becoming flakey and cannot retain the setting, even during the ride. Hit a bump, and suddenly it’s in flashing mode or dimmed. I know there are two circuit boards in the light: One at the front that drives/regulates the power to the LED, and the other that is at the push-button switch end and has all the special functions.

Question: Has anyone bypassed the switch? My system is already wired to have ON/OFF power at the handlebar, so the 5-way is not only redundant, but unnecessary.

Thanks, KF

 

[Kin]

It's not clear to me what you're asking...but maybe I'm just extra dense/out of the loop.

I thought you were asking about bypassing a 5-way switch, but I also think you are saying you have done that already.


Is it even a 5-way switch? most lights I've seen simply cycle electronically, it's not a physical 5-way switch. But although I could be mistaken, I assume they would integrate whatever MCU that decides the mode, with the MCU that controls the power drivers. Are you sure the first board is only a switch selection board?

You might find some info on http://www.candlepowerforums.com/vb/content.php or one of the other flashlight enthusiast sites.

 

[cwah]

I was thinking about doing the same thing. My wires have snapped and now it's not working anymore.

I'd like to completely remove the board and transformer, then directly connect it to the + and - of the light with the 12V DC-DC converter. Not sure if the light will be able to handle that thought.

 

[Kingfish]

>> Kin: Understood – allow me to be more clear… I modified the lights previously so that the power is provided by my DC-DC converter and replaces the battery – thus leaving intact the flashlight electronics.

To restate: I want to bypass the push-button switch, hardwire it so that it is always ON.

Ref: Cree HP-LED Conversion & DC-DC Converter Assy

~KF

 

[snellemin]

You can direct drive them if that is what you are asking. I've done it with my cree and bootleg cree lights and just have a switch turn them on. I'm running two in series hooked with a 2s3p 18650 battery pack and a switch mounted on my handlebar.

 

[Ypedal]

I know exactly what you are asking, and am wanting to know the same things..

1- can LED's be driven directly as long as you have the voltage right ? or does the current need to be regulated ? ( for some reason, i could swear i've read that the Cree's need current limitting or they fry themselves )

2- the 5 mode thing is via using the partial press of the on/off button, toggles between modes, i'd love to bypass this somehow on a few flashlights i have here with that problem ( hit bump and they change modes )]

it's not a physical 5 position switch, it's " 5 modes " push button like on the CA that switches screens when you press...

 

[MattyCiii]

I know exactly what you are asking, and am wanting to know the same things..

1- can LED's be driven directly as long as you have the voltage right ? or does the current need to be regulated ? ( for some reason, i could swear i've read that the Cree's need current limitting or they fry themselves )

2- the 5 mode thing is via using the partial press of the on/off button, toggles between modes, i'd love to bypass this somehow on a few flashlights i have here with that problem ( hit bump and they change modes )]

it's not a physical 5 position switch, it's " 5 modes " push button like on the CA that switches screens when you press...

You can do some real crude voltage regulation based on what you plug into where. I've been running Cree & other LEDs straight off LiPo. If you give it too much voltage, it'll be brighter, but get hot, eat the amps and kill the LED quickly.

Through lots of reading, some dubious thinking, and some trial/error/error/success, I've found that you can drive 1 super bright white LED off 1s LiPo and do real well. You can drive 2 series red LEDs off 1s and do well too. Bright light without a lot of heat. Long life, both in terms of hours per charge and in LED life.

This works great in a couple ways. I have a Light & Motion Vis 360 head light for my bike helmet - bright white front, blinky red rear, cost me $150. In winter, I have a homebuilt setup on my motorcycle (winter biking) helmet, bits & pieces from deal extreme.com: 1 white light forward, with mirror reflector, in parallel with 2 x red LED's rear, driven off 1s LiPo cell taped to the helmet. Cost me like $20 total.

I also run a pair of red LEDs as rear lights on the bike off another 1s LiPo pack, attached to the bike. Runs like a month between charges. I just test it once in a while with the multi tester and recharge with the iCharger & alligator clips.

red LED emitter, $3.64
White LED emitter, $4.20
Reflector housing, used for forward white light, $2.76

Pretty neat having the DIY, cobbled together stuff. Problem? Get the multi-tester and soldering iron. The expensive, integrated Light & Motion system? Fine too, but it died in Jan, out of warranty. I sent it to them to fix, it cost me like $70, plus ~3 weeks without a light while they turned it around.

 

[cal3thousand]

The switch is not 5 way. that function is included in the driver. All you would need to do is run a different driver chip.


The switch is just a simple clicky switch that will allow a soft press that momentarily breaks the circuit, which tells the driver to switch modes. When you are riding and it switches, it is because a break in the circuit is occuring for a short (milli) second. Resoldering the driver to LED and driver to cell connections might fix that issue.

If not, DX would have many options you can use depending on your input and output requirements.

 

[Kingfish]

The switch is not 5 way. that function is included in the driver. All you would need to do is run a different driver chip.


The switch is just a simple clicky switch that will allow a soft press that momentarily breaks the circuit, which tells the driver to switch modes. When you are riding and it switches, it is because a break in the circuit is occuring for a short (milli) second. Resoldering the driver to LED and driver to cell connections might fix that issue.

If not, DX would have many options you can use depending on your input and output requirements.

I have to concur with you.

I followed this thread, removed the clicky and tried the direct connect using a common 10-cent Dime: The 5-way is in the other circuit board. I can however bypass the flakey clicky, so that’s part of the problem resolved. Except – I have two LED lights, so flipping the bar-mounted switch ON/OFF will likely produce unsynchronized engagement.

Buggery. Now to replace the Driver Board.

Grumbles, KF

 

[cal3thousand]

The switch is not 5 way. that function is included in the driver. All you would need to do is run a different driver chip.


The switch is just a simple clicky switch that will allow a soft press that momentarily breaks the circuit, which tells the driver to switch modes. When you are riding and it switches, it is because a break in the circuit is occuring for a short (milli) second. Resoldering the driver to LED and driver to cell connections might fix that issue.

If not, DX would have many options you can use depending on your input and output requirements.

I have to concur with you.

I followed this thread, removed the clicky and tried the direct connect using a common 10-cent Dime: The 5-way is in the other circuit board. I can however bypass the flakey clicky, so that’s part of the problem resolved. Except – I have two LED lights, so flipping the bar-mounted switch ON/OFF will likely produce unsynchronized engagement.

Buggery. Now to replace the Driver Board.

Grumbles, KF

They are cheap, but you will have to wait for shipping from DX, which takes for ever.

You might be able to find a quicker source. I have some of these on hand, if they work for you, I could sell you one (but it's still a 5 way switch):

https://www.dealextreme.com/p/3-6-8-4v-5-mode-3w-circuit-board-for-flashlights-1000mah-3-7v-output-7425

I also think that resoldering the connections in and out of the driver might actually help. And of course, as suggested by someone else, you could rig up a temporary crude circuit to drive the LED directly at 3.7v and control the current.

 

[Kingfish]

I don't buy from DX after a really piss-poor experience waiting for-fking-ever for product to arrive.

Found these guys instead: Dia. 16mm LED Buck Voltage Regulated 1-Mode Flashlight Circuit Wafer 700mA~1000mA @ 3~10V (5PCS) for USD $9.32 from AliExpress.Com

Anyone do business with these guys? There's Qty-5; I only need three. Group buy? :wink:

~KF

 

[cal3thousand]

I don't buy from DX after a really piss-poor experience waiting for-fking-ever for product to arrive.

Found these guys instead: Dia. 16mm LED Buck Voltage Regulated 1-Mode Flashlight Circuit Wafer 700mA~1000mA @ 3~10V (5PCS) for USD $9.32 from AliExpress.Com

Anyone do business with these guys? There's Qty-5; I only need three. Group buy? :wink:

~KF

I've never bought anything from AliExpress.com ... isn't that just a bunch of resellers/manufacturers in China directly?

 

[Kingfish]

Yes, but aren't they all?
Zero difference between DX and DinoDirect - except with the latter you actually get the product in a timely fashion with a tracking number. However, the Search feature in DinoDirect bites.

More on kaidomain.com - dig the fuzzy pictures <not!>

There's another problem: The emitter is epoxied to the aluminum can and the it's not entirely obvious how to remove the driver board. Looks like it's soldered. Might have to experiment...

...KF

 

[amberwolf]

1- can LED's be driven directly as long as you have the voltage right ? or does the current need to be regulated ? ( for some reason, i could swear i've read that the Cree's need current limitting or they fry themselves )

All LEDs are current-driven, so you have to ensure you don't exceed their current maximum spec or you risk damaging them. The closer you get to that max the shorter their life, too; past that limit and they could last years or seconds.


They also have a minimum turn on voltage, but the important thing is to limit the current thru them.


An LM317 can be used as a current source, there are numerous schematics on the web to do that (just image search that phrase). As long as your input voltage is no higher htan the max LM317 spec, it'll work fine, though it will waste power as heat as it is a linear regulator.

The SMPS regulators like the little boards that come in these things are way more efficient, but they do add complications that can cause things to fail. (and often, features you don't want like the button sequence press to turn them on to the right mode).

 

[texaspyro]

If your LED is or can handle 10 watts try one of these:

http://www.ebay.com/itm/10W-LED-Driver-DC8-26V-AC-DC-12v-For-10-Watt-LED-Light-/280699545136?pt=LH_DefaultDomain_0&hash=item415aff2630

 

[Kingfish]

FWIW, I found a single-mode replacement of my units from DinoDirect:

• UltraFire™ WF-501B CREE XPG R5 1 Mode 350Lumens LED Flashlight (1*18650)

My thoughts are to gut the assembled emitter/driver unit and plug it into my existing one; cheaper faster better than me dorking around - that and the physical specs are nearly identical to what I have now.

This has been a good exercise. Doesn't seem like much has changed with this technology except more packaging wtih multiple emitters.
~KF

 

[cal3thousand]

If your LED is or can handle 10 watts try one of these:

http://www.ebay.com/itm/10W-LED-Driver-DC8-26V-AC-DC-12v-For-10-Watt-LED-Light-/280699545136?pt=LH_DefaultDomain_0&hash=item415aff2630

10W is a sh*tload for LEDs. At 3.7V, that's 2.703 Amps... LEDs run waaaaaay less current than that. Would need parallel emitters... many.

 

[cal3thousand]

FWIW, I found a single-mode replacement of my units from DinoDirect:

• UltraFire™ WF-501B CREE XPG R5 1 Mode 350Lumens LED Flashlight (1*18650)

My thoughts are to gut the assembled emitter/driver unit and plug it into my existing one; cheaper faster better than me dorking around - that and the physical specs are nearly identical to what I have now.

This has been a good exercise. Doesn't seem like much has changed with this technology except more packaging wtih multiple emitters.
~KF

BTW, i just ordered some stuff (including a Imax B6 with AC input for $36.20) from DX.com. ... same prices BUT from a US WAREHOUSE!!! I wonder if this bypasses all the waiting crap and the Lunar New Year dead period

 

[amberwolf]

10W is a sh*tload for LEDs. At 3.7V, that's 2.703 Amps... LEDs run waaaaaay less current than that. Would need parallel emitters... many.

That would depend on the LED...there are some out there that coudl blind you (literally) if used at max specs. I supsect most of them are multichip arrays in one package, but I saw one out there last year that did not appear to be, and was intended for overhead spotlighting (as in, street light type spotlighting, for road workers). I cant' find it now, of course, but I think it was in a thread here on ES.

 

[Ypedal]

that 12v 10w driver looks right for this sucker..

 

[Ypedal]

3 of these in series.. i've tested using 4 cell lifepo4 straight up.. works.. but the heat sink gets hot.. FAST...

 

[texaspyro]

10W is a sh*tload for LEDs. At 3.7V, that's 2.703 Amps... LEDs run waaaaaay less current than that. Would need parallel emitters... many.

Not at all, Cree XM-L's can run at 3.5A. Luminus makes some that pull over 10A. I have a Bridgelux array that I drive at 150 watts (30.9V/5A). 10 watt arrays (usually 3x3) are quite cheap on Ebay... but, always, beware of Chinese bearing specs...

See: http://budgetlightforum.com/node/2603

That driver is probably OK for a 3 LEDs in series.

 

[texaspyro]

3 of these in series.. i've tested using 4 cell lifepo4 straight up.. works.. but the heat sink gets hot.. FAST...

You should drive it with 3 LiFePO's. They typical LED Vf matches up to LiFePOs nominal voltage quite well.