Boost LED driver

[Michael.su]

Hi everyone,

This is my first post because I'm a new LED tinkerer. :D

I'm building an LED bike light for trail riding at night.

I am having a hell of a time finding the right LED Boost driver.

The battery I want to use is a 7.2 v 3300 Mah NIMH (RC car battery)

For the LED's, I have a Luxeon 3 Rebel star.

http://ledsupply.com/07007-pwc-08-3.php

The LED's require 9.45 forward voltage.

Any help would be greatly appreciated...

Thanks,

-Mike

 

[znomit]

Maxflex
http://www.taskled.com/maxflex.html

:welcome:

 

[Michael.su]

Thanks for the recommendation. that looks like it will do the trick!

-Mike

 

[yellow]

caution!

Maxflex offers much options, but is also difficult to understand and needs an additional pushbutton switch (together with the main power switch).

another step up driver were the SHARK form Sandwich Shoppe,
programmable with external poti (or better a few resistor values changed by a switch)

then there are a multitude of step-up drivers at Dealextreme and Kaidomain and ...
(You get what You par for!!)

 

[Goldigger]

Here's a guide of one of trouties light builds that uses a maxflex..
He only used a momentary switch for this build... Maybe if you drop him a mail or a pm he might help you setting up the maxflex..
http://www.troutie.com/XPE BUILD TUTORIAL.html

 

[georges80]

caution!

Maxflex offers much options, but is also difficult to understand and needs an additional pushbutton switch (together with the main power switch).

another step up driver were the SHARK form Sandwich Shoppe,
programmable with external poti (or better a few resistor values changed by a switch)

then there are a multitude of step-up drivers at Dealextreme and Kaidomain and ...
(You get what You par for!!)

Ok - this is a bit funny... You say you need an additional push button switch for maxflex and then mention using a shark and adding some external resistors and switch or external Pot.

Why do you need a main power switch for maxflex? It only draws <0.05mA when turned off via the momentary switch. If we assume a 2amp.hour battery, that would be 2/0.00005 hours before the battery was flat. So, 40000 hours or 1666 days. You think a power switch is necessary???

Maxflex gives you a lot of features that make a lot of sense for a bike light - especially the voltage warning/monitoring stuff. I personally wouldn't ride a bike at night without at least some idea of the state of charge of the battery.

Yes, I agree it can be relatively complex to configure the first time, but after that all you need to do is click it on, click to change levels and push to turn off.

For the OP, maxflex comes preconfigured for a 2 li-ion pack as far as voltage monitoring, so for that part he wouldn't need to make any changes via the menu system.

The maxflex firmware features were in part a result of folk here on CPF and on MTBR offering their input on what they felt was important. With 1000's of maxflex/bflex/hipflex drivers in the field I have only had a handful of questions on setting things up and generally it is just a confusion about how to enter the menu system

Anyhow, just trying to put things in perspective.

cheers,
george.

 

[Linger]

Mike,
what do you want the lights to do?
Bright contast on?
blinking?
Low, Med, High?
Medium, blinkingfull power, blinking 1/2 power.
Continuously variable?

Congratulation on makeing the step to build your own bike light. You've got more freedom now they $1000's could get you with commercial products. The biggest problem comes when poeple see how else they could have done it.
For example, spending $3 on a multi-mode driver and cursing for not buying a more expensive model with thermal protection and low voltage cut-off, or spending $45 dollars for a programable driver when a the $3 driver had all they needed and they ended up ripping the whole system appart to rebuild with magnetic charging and sst-50's

Taskled has excellent reputation, i haven't found a multimode board from them that I like yet so no first hand exp. If you really find something you like, I strongly recommend you start talking to them about it, while youve bougt another board from DX or Shiningbeam.
Make one or two fairly cheap ($30 in parts). The more experience you get making lights the higher the production values you start putting in.

Shiningbeam is best for me, they have items are request with fantastic follow-up support. low cost for high quality boards.s

 

[yellow]

good answer ;)

ok, I would use a main power switch, because I think doing that with just the connectors to the batt pack is not "good".

Programming, or understanding Manual of Maxflex, is somehow difficult. As there are so much other things to consider, maybe a bit too much for someone starting with light building?
Sure it features a lot and is great (I have three here, all about to be put in their mods).
My advise to Michael: check the manual and decide then

on the other hand, adding an additional pot, or a vew strings of different resistor values with a rotary switch is nothing for someone who already is a bit in soldering/electronics

example of a 4-position rotary switch that makes on/off (with pins of "A" and "B") and gives the choice of three levels (pins of "C")

... its maybe more "low-tech" to use resistors instead of a progrmmable driver, but there is also a different level of knowledge/wants with the light builders