No more VIP's... Now what?

I'm planning a build where I was going to use the VIP but, alas, they are no longer. This VIP seemed like just what the doctor ordered: 2x1.2V cells, 1000mA output. Shazam!!!

Well, I'm finding that the VIP is no longer, so I'm on the hunt for alternatives. Single function is preferred. Simple on and off is just fine for me. I've found micropucks, flupics (although multi-mode), drivers from the Shoppe, and others... Problem is making a choice.

Plans are for a Mag 2C host, a DHS like this and some animal of a LED (whatever is out there at the time it all comes together).

Simple is good at this point... Suggestions welcome.

Assuming a single led, with (2) Nimh cells I would say one of the drivers from the shoppe (ie Badboy, BB Nexgen). You are within 1 volt of the forward voltage of most of the readily available leds (P4, LUX III) so there isn't much step/boost required.


If you could change the batteries to rechargable li-ions, the options would increase. You could then go to a buck or step down converter. If it were me, I would go with a (2) 18500 protected li-ions and a bflex driver from TaskLED. It isn't as simple but it is a great light in the end.

Hope it helped and good luck,
Chris
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Did George recommend a substitute for the VIP? I know I got some of the last ones and love them. I also agree I wish they were being produced still.

I think if you email him you should be able somewhat get a VIP out of the current Fatman, but don't bother with the dimming capability.

Bob E.

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The energy density of the Li cells is fantastic, and the voltage is indeed attractive. However, I'm a bit leery of the volitality of the chemistry. Yes, protected cells are available and if you're careful, lots of fun can be had for a long time. But, if my wife ever goes to use the light, and isn't aware of the need to be "careful" (she subscribes to the bigger hammer theory) - well, the party is over.

Flipside, forgot to add that although you may not get your full 1Amp out of Micropucks, if you look on their applications sheet, you can parallel two of them for 800mA. So far, I have two lights setup this way, on Seoul P4 and one Cree Q5. Bright, easy, foolproof. Efficiency is somewhat an issue, but big D rechargeables and unlimited alkalines around, I am willing to trade efficiency and ease of build for a longer lasting light.

If you have some extra time and money, I used a BuckPuck with 9xAAs with a fancy dimmer (from them) and have not had the time to see if a BoostPuck would work with two NiMH cells (mainly D's) and one cree or seoul driven at 1000mA. I have a Boostpuck on order but it hasn't arrived yet so I can't tell you if it will work or not with 2 NiMH batteries.

I can certainly tell you this. With the Micropuck, Buckpuck, or Boostpuck wiring will be extremely easy. You won't need magnifying glasses to solder small wires into small holes that are around even more small electrical stuff. I just wish they would make a 750mA Micropuck or a 1000mA micropuck that we could use to simplify things for high power LED flashlights.

Bob E.

You might find this thread useful.

I'm with Bob here. If you want one level, easy to wire, go for two Micopuck 500mA drivers. You should get 750 to 800mA. I don't think you would notice much between 800mA and 1A.

Let us know how you get on.

SafetyBob said:

I just wish they would make a 750mA Micropuck or a 1000mA micropuck that we could use to simplify things for high power LED flashlights.

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My feelings exactly... While the efficiency of the pucks isn't the greatest, they're within what 10-15% of what the VIP or similar drivers were doing. Over an hour's run time, it doesn't amount to much - what, 5 or 10 minutes?

The pucks are looking like the way to go. They're about 200mA below of my target, but maybe that will help in the life of the LED...

Essexman said:

You might find this thread useful.

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Indeed... Fantastic! Perhaps it'll be a sticky?

Thanks for the link.

SafetyBob said:

Did George recommend a substitute for the VIP?

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Bob,

In fact, he responded as follows:

"yes, the VIP driver is no longer available and I don't have parts to build more and no intention of reviving that project. The boards I had were left overs from the VIP light project of several years ago and when they were sold out - that was it. The VIP driver wasn't a big enough seller to justify making more.

I don't have a driver that would boost from 2 nimh cells and drive a single LED. All my boost drivers are intended for multiple LEDs (or at least a 5W LED)."

I asked about multi-LED arrangements with a 2x NiMH and he came back with:

"a pair of nimh cells won't work with any of my boost drivers. They would need a minimum of 3 or a single li-ion driving 2 LEDs etc etc."

George, if you're reading this, thank you for your responses and comments. Keep up the good work!

I think this setup would work:

NiMH cells (1.4 volts fresh off charger)
Shark Driver from the Sandwich Shoppe
Seoul USWOH emitter
FiveMega LOP reflector

You'd have to ask Wayne at the SS, but I think that driver would work fine, but only with NiMH cells. Forget about alkalines in a 2 cell light.

That is too bad that George won't make any more. Perhaps if we can get 100 orders or so on the ready, he would change his mind. The way I feel about the VIP, I would buy 10 of them right now if they were available. They make such a nice 2 battery flashlight.

As Essexman indicated, with two of the MicroPucks (the SHO version @ 500mA) paralleled you would get that 750 to 800mA and I agree that you would probably be hard pressed to tell the difference. Building two that way right now as we speak for birthday presents. I don't think you will ever know if there was any life difference between 1A and 800 or even 750mA. They are all within the allowable spec for the led.

If you want that "real" 1A, then by all means talk to Wayne at the SS and then tell us what he says. There are alot of us out here that want the steady 1A single power level for our lights (no bells, no whistles) and it is getting hard to find that solution....ok, quality solution like there was with the VIP.

Let us know what you end up doing. I will be following this with great interest.

Bob E.

Someone needs to build a driver around the Linear Technology LT1618. You could get pretty much any current you want (up to ~2A) from a 1.6 to Vf voltage source.

Good call Stereodude, and you bring up our biggest problem here. Since most of us are not electrical engineers or even that good of electrical hobbiests, we cannot really do this by ourselves.

I know we could probably get one of the EE types here to design a circuit, actually do everything for us preproduction, but then we would have to have them made for us. I would think that might get pricy. I look at all the small stuff on George's VIP boards and don't even want to even get close to it with a soldering iron let alone try and actually place that stuff correctly on a board.

The main problem is we would have to almost have a series of boards made to accomodate the various battery senerios we will want. Maybe a good EE could work around that if powering just one LED at 1A. But with 2Amps, man I can see a really nice tri-cree shaping up.

Bob E.

Stereodude said:

Someone needs to build a driver around the Linear Technology LT1618. You could get pretty much any current you want (up to ~2A) from a 1.6 to Vf voltage source.

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Here's the spec sheet... Trouble is, even when I turn my monitor upside down, I still don't understand it. :thinking:

Just where am I supposed to connect the doo-hickey to the what-cha-ma-call-it, and how big a hammer do I need to hit it with???

Damn, I knew I shouldn't have skipped class that day.
Anyway, a MECHANICAL engineer like me hasn't got a chance with this thing. Anyone else care to take a stab at it???

Flipside said:

Here's the spec sheet... Trouble is, even when I turn my monitor upside down, I still don't understand it. :thinking:

Just where am I supposed to connect the doo-hickey to the what-cha-ma-call-it, and how big a hammer do I need to hit it with???

Damn, I knew I shouldn't have skipped class that day.
Anyway, a MECHANICAL engineer like me hasn't got a chance with this thing. Anyone else care to take a stab at it???

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I'm a EE and I've worked with a lot of Linear Tech parts including LED boost drivers. I've looked at the data sheet and the ap notes. The problem is that this datasheet is missing some necessary information. I believe I made a mistake in my earlier statement of the current output of the device. It gives a maximum current of ~2A, but after a closer look that's the internal MOSFET switch in the part. Output current is lower than the input current, especially when the batteries are low. The issue is that the datasheet is missing the formulas to calculate the output current based on the maximum current of the internal switch. I'd have to go digging into some other datasheets to confirm, but from my memory I'd say the maximum output current (assuming a Vf on the LED of 3.7V) will end up being around 1.6V*~2.1A*85%/3.7V = 770mA.

I started another thread here to take this to the next level... If you'd like to express interest in a VIP or VIP replacement, please visit this thread.

Do we know what IC is on the VIP driver? That would be the best place to start.

I am a first time poster and also have the EE background. I have had great success with National Semiconductor and their products. I have been able to get samples and they have always sent them quickly. I was looking at their LED drivers http://www.national.com/appinfo/power/led.html and I think their new device LM3410 would be a great fit for many applications (I would be curious as to what Stereodude thinks as I have not been into moding flashlights before). The package is a small 5 pin surface mount and allows for external control. It is fairly efficient, and can provide 1.5 Amps. Their datasheet provides ample background information.

National Semiconducter also has online design software for developing projects using their silicon. The link to their WEBENCH software is here
http://webench.national.com/appinfo/webench/scripts/my_webench.cgi
Just register for there site and off you go, it will design the circuit for you based on Vin/Vout and Iout and even provide a layout for a demo board. I like the application because it will let you know how much heat sinking you may need to provide and how close your decoupling capacitors should be to the driving device. Although they are a little slow on updating their design database for new products.

I would be curious to know what devices are primarily being used in most drop in modules ( but I don't have any), and also what devices are being used to control the driver, ie PWM Chip or microprocessors! I am more interested in the development of efficient controllers that provide greater runtime then max power controllers.

Ok sorry for the interjection, back to Lurking :wave:

The LM3410 looks OK from a device standpoint, but it is not suitable for a VIP type driver (2 NiMH or Alkaline cells).

Stereodude said:

Do we know what IC is on the VIP driver? That would be the best place to start.

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Linear's LTC3402. Let me know if you need schematic info or any info on the other parts.