Buck and Boost Drivers, Testing, Modding, and Discussion (Pic Heavy)

So could the 555 timer circuit be added to a cut pin 5 trace for variable brightness or does it not apply to this circuit.
I think you have a little more electronics back ground than me, that’s the reason for asking.

Thanks. Don’t mind loosing charging but the UI is a pass for me too. What’s the sticking point for those working on making them? To a complete layman? Keeping the voltage boosted while all the possible clicks/outcomes?

This is what I had in mind, and also would like to know if it’s possible with this driver.

I really don’t have much of an electronics background. I know a little about FET drivers, but just the basics of Boost and Buck

I know some boost drivers are designed to accept pots to control them (like this one), but the HA1 is not one of those. I believe your talking about cutting the PWM output trace to the OPA333 and adding a new opamp that can be controlled by a potentiometer. Maybe it can work? It is beyond my knowledge.

Such dimming would be very helpful for my application. The H1-A fills a huge void for when having to operate 6v LED with 1S batteries. There are few to no other options.

My application is a bike light, specifically a IQ-XE light. The unique efficient design has the best cutoff for no glare onto oncoming traffic without losing lumen. But the design requires the use of a double LED encased in series in one tiny unit (OSLON Black Flat KW H2L531.TE) nominal 6V, 1.5A peak, and this light operates at 0.9A max.

The driver in this light is inefficient and could use a boost in output. It also requires 12v input and I want to stick with 1S batteries without having to deal with balancing. So I gutted it and added the H1-A driver. I modded the H1-A to operate at 1.2A and I got much more output at the same net energy consumption at the battery, and with 1S. So I was very happy, until my shoddy soldering work failed. So I’m attempting it again with another H1-A.

My application doesn’t require the driver to fit within any confined space, but it does need to be lightweight, and the H1-A is perfect. It would be nice to explore dimming options with a potentiometer (555 timer?). I came across another driver I’m curious about which seems to operate on the same principles as the H1-A, using a XL6003 IC. The particular driver doesn’t have dimming but the IC supports it. I don’t know enough to know how the design compares to the H1-A.

https://www.aliexpress.com/item/32918936790.html?spm=a2g0o.productlist.0.0.5df55ee0VkHvUr&algo_pvid=fa12217c-7f1a-46c2-92c2-4e75097f2dba&algo_expid=fa12217c-7f1a-46c2-92c2-4e75097f2dba-0&btsid=15072488-fcb8-4cea-b054-c20cc0282ef7&ws_ab_test=searchweb0_0,searchweb201602_5,searchweb201603_52

I just saw you link to the hyperboost driver. That just might be the ticket. I’d have to give up on 1S for that driver and go with 3S. I’m considering it.

Edit: hyperboost won’t work with less than 8V.

Part of it is building the driver to give high output, without burning the pcb traces. Plus you have to address any ripples or surges in the circuit. Test, redesign, test, redesign until it works smoothly with no weird hiccups. Then when that it done you need a computer programmer to adapt an existing UI to work with the boost controller. Toykeeper told me she helped Lexel get NarsilM working with his boost driver design about 12 months ago, but he still hasn’t released anything yet.
These 2 guys, Lexel and Richard at MTN E, are basically designing and testing these drivers in their spare time from home while filling orders of existing drivers, working with OEM’s (Lexel) and running a store (Richard). Their current work is what pays the bills. Designing a whole new type of driver (Boost) is costing them time and money from their own pockets, so their progress is slow. I thought Lexel was close to releasing his about 18 months ago, but nope.

The particular light I was wanting to build was to convert my Supfire L5-S from FET to Boost to limit output on Turbo and switch from 2 x 26350 cells to a single 26650. I bought a new host and everything and it’s been collecting dust for 18 months. Luckily Sofirn released their version 2 of the SP33. It is a sweet boost driver light that has filled the role of the L5-S, so I’m no longer in a rush for a boost driver. I’m just chillen. They will come out when they come out.

That looks like a neat design, but it’s dynamo powered? I guess it runs off the turning bike wheel? Seems odd.

Have you seen Lumintops new bike light, the B01 It’s a similar lens design, but cheaper and uses a 21700 battery. Plus it’s USB rechargeable so you should be able to plug in a power bank to greatly extend run time. Your spending a small fortune on modding that IQ-XE. It might be time to cut your losses.

The IQ-XE is entirely different league when it comes to a most lux at distance with distinct cutoff line for least lux up onto oncoming. The best comparison is the Lupine SL with broader and more even coverage, which many prefer over IQ-XE, but not me. We have very bad roads here and I need to see those potholes well ahead of time and the IQ-XE is the most efficient at putting lux right at the cutoff line directly ahead. The IQ-X is the dynamo version and IQ-XE is Ebike version. Had both. Same except for internal drivers. Dynamo version is cheaper, so it’s better for driver modding. When modding for higher output, also best to bond the LED assembly to the housing for better cooling of the LED. BTW, IQ-XE is already more than enough for just about anyone, but I can never turn down opportunity for improvement, and this mod does wonders.

I’m building the battery pack with regulated DC input for expansion and charging, and 5v DC output for phone charging while on the go. I wouldn’t venture OT but this is your thread, so I’m glad to expand.

I’ve messed with a lot of projector retrofits with hid when they started to be more common 15 years ago and recently started studying led versions of projector and even reflector housings. I love projectors for their sweet cutoff lines and very usable light on the ground.

These 90° led/reflector designs are still pretty new to me. I see them popping up here and there. Do you think their beam shape beats a projector housing?

I have seen these 90° led/reflector designs (do they have a specific name?) in aftermarket fog lights. I wonder if the design will be adapted into a OEM car headlight design soon.

Automotive is easy because efficiency isn’t detrimental. So simply blocking of the top half of the light works, and has inherent high beam built right into the same unit. European restrictions on bicycle lights has driven the market to create new ways to illuminate only the lower half without losing efficiency under small battery operation, and without need for high beam.

For what it accomplishes, I think the 90° design is genious. But because the automotive projector design is so simple while having inherent high beam, I don’t think it’s going to be replaced by the more efficient 90° designs soon, but it’s possible. Saving a few watts in automotive probably makes less difference than having a bug on the windshield.

However, you may find the Lupine SL interesting, as it’s an implementation of the 90° design in a projector configuration. That’s what makes it a much more pleasing beam pattern than the IQ-XE, but also what makes it have less peak lux.

Doh! :person_facepalming: I forgot these new 90° designs can’t change to create a high beam. Still, a lot of cars use dual bulbs per side, one projector for low and typically a reflector for high beam. So still possible.

Maybe it’s just cost. I know projectors can have the cutoff line easily changed for left or right hand drive countries as well as special shapes. You just change the stamped metal shield. These new 90° designs might require more extensive modification (more :money_mouth_face: to adjust the cutoff line.

Automotive OEM’s have not really embraced led headlights anyway. There are a few ultra expensive led designs out there (mainly prototype designs), but I bet projectors are just way cheaper.

Those 90° optics are new to me. I’m not sure I understand what exactly is going on in them. Has anyone seen some writup or a schematic on them?

Many years ago I was following the first experimenter of this design on mtbr.com (who doesn’t get the deserved credit imo). He was using portions of a large reflector to piece together the concept, somewhat crude but ingenious and it worked. Soon after, Edelux came out with the first commercial light with a reflector created specifically for the design, followed by many others. The first Edelux angled the LED at 45-degrees. Over the years there were many improved generations of these lights with the current IQ-X using 90-degrees, in which a convex combined with a reflector utilizes the light more efficiently.

Edelux Design

IQ-X / IQ-XE (Google-Translated Version)
The convex lens and double “series” integrated Oslon LED seen in last photo of post. The OSLON Black Flat KW H2L531.TE

Thank you, that’s interesting :slight_smile: . I’ve seen Endermann calling that off-axis parabolic reflector.
It clearly works well with headlamp LEDs which are often sold pre-mounted as several-in-a-row configurations. That seems to be what IQ-X is using.
Any more info of Lupine SL A projection optics?

ADDED: Though I still don’t understand that IQ-X convex lens.
Is it used together with the reflector?

See the Lupine SL here
The side view is clear it’s a convex lens that refracts all of the output from ceiling-mounted LEDs.

Yes, The IQ-X convex lens only refracts the forward-emitted output, and rearward-emitted output is reflected off the reflector.

The Philips Saferide was the first to use multiple LEDs early on. Here’s some good history.

Edit: Note that the IQ-XE consumes less than half the watts of the Lupine SL, but produces more lux at the cutoff line. I do very long night rides on bad roads, so in my case, the IQ-XE is much more proficient. The Lupine SL puts a lot of light to the sides, which is especially nice for off road. But my friends and I realized we like light only on the roadway directly ahead and the least amount of light spill, because spill light kills the ambience of the ride. Just a preference.

With aftermarket LEDs that take the place of a filament bulb in a reflector based housing, they put 3 or 4 chips next to each other to simulate the size and shape of the filament. The reflector is specially designed to focus light from that grain of rice size light source.

With the new 90* reflector designs, they are creating a string of light for other reasons. They can probably use any shape they want, but the thin string probably helps give a wide view with sharp cutoff. They are starting with a clean design as opposed to adapting to an existing reflector.

We don’t have strict bicycle headlight laws in the US so I never even looked into the market. Here people just strap any old flashlight to their bike and blind everyone. Lol.

We might be getting a bit too off topic now.

Double LEDs create horizontal off axis, which spreads the beam pattern horizontally. Bringing this back around, you can see the need this creates for drivers like the H1-A.

They just need to wire the leds in parallel.

Not sure if it’s right thread to ask. but is there any way to know which resistor is responsible for output current in below driver -

this is a from a 13w motorcycle headlight, designed for osram black flat leds (looks like it). output current is 1.5amp. but i want to increase it to 2.5-3amp and replace led to whiteflat.