Irakongi driver: Information and Interest

This thread is to provide information regarding two new drivers. Both drives will be initially released in a box configuration that can be mounted to the Makita LXT battery dock or used without the battery in other applications.

Here is a picture of the Makita LXT battery dock interface.


The driver will reside in a custom plastic enclosure that mounts on top of the Makita Battery dock.


A view with the box open.


Topside labeling and holes for the box lid.


Completed assembly view.


In this configuration there will be a buck driver and a boost driver.

For now they will be called Irakongi-buck and Irakongi-boost for lack of better terminology.

Preliminary specifications:
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Irakongi-Buck:
Vin Range: 10V-36V
Output Current: Set by one sense resistor (default 1A)
Maximum Input current: ~3A
Maximum Input Power: ~50W
Open Circuit protection: Yes
Thermal foldback: On board sense resistor (can be removed and put on LED heat sink)
Number of Output levels: 3
Output drive levels: 100%, 50%, 20%
Maximum output level: Set by one sense resistor
Output voltage level range: 4V to Vin-1V.
Board Dimensions: 2.3" X 2.1"
Price: TBD
Availability: hand built protos over the next few months until demand warrants production

Irakongi-Boost:
Vin Range: 10V-36V
Output Current: up to 3A
Maximum Input Power: 50W
Maximum Output Voltage:~50V
Open Circuit protection: Yes
Thermal foldback: On board sense resistor (can be removed and put on LED heat sink)
Number of Output levels: 3
Output drive levels: 100%, 50%, 20%
Maximum output level: Set by one sense resistor
Board Dimensions: 2.3" X 2.1"
Price: TBD
Availability: hand built protos over the next few months until demand warrants production

Box dimensions:
3.3" X 3.3" X 1.25"

Board dimensions:

Rotary switch panel hole size: 0.26"
LED mounting hole: 5mm
PCB mounts (2): #6 hardware

========================================================

Example 1: Two 6 die Ostars

First: LED power must be ~40W or less. Two 6 die Ostars @ 1A is around 42W. Close enough.

Next: Determine the Vf of the LED string. Two Ostars ~= 21*2 or 42V. Since 42V is less than the specification of 50V this is acceptable.

Next: Buck or Boost? What battery will you be using? In this example we will be going with the Makita LXT 18V power pack. Maximum is 21V and minimum is around 16V. For both ends of the power pack are less than the Vf of the LED string we need the Irakongi-Boost driver.

I would mount the thermal sensor to the LED heatsink for thermal foldback.
(Note: If each LED are in different heads or heatsink, mount the sensor to one or the other).


Example 2: Two P7 LEDs.

Two P7s at 3A (4V Vf) is 24W.

If Battery source is the Makita LXT (16-21V) we need the Irakongi-buck converter. Change the sense resistor for a 3A output max output.

Again I would mount the thermal sensor to the LED array or heatsink for LED thermal foldback.

Example 3: 12 Cree LEDs @ 1A. Something like 10 whites and two reds might give a good high CRI LED cluster. This configuration is basically identical to the two 6 die Ostars.

=====================================================
The driver will most likely come in the box shown since the three level switch that is mounted to the PCB needs to mount to something. The box provides mechanical mounting of the PCB and can easily be adapted to ones individuals needs. The box bottom is blank. Mounting to the Makita dock requires drilling out the appropriate holes to mount the box to the Makita dock.

Example 1 and 3 could be run off a 12V power supply, vehicle cigarette light er plug or off a 24V wall adaptor as well as the Makita LXT battery.

Example 2 could run off the Dewalt 36V power pack as well as the Makita LXT power pack.

related Links:

Makita LXT with Dual Tri-Rebel head


Wayne

Re: Irakongi driver: Drives two Ostars

Reserved

Re: Irakongi driver: Drives two Ostars

Nice Wayne. I assume the box will mount on top of the CreeBar as well as on the dock? I think for some applications it would be nice to have the CreeBar as a heat sink for the power likely to be involved.

Re: Irakongi driver: Drives two Ostars

McGizmo said:

Nice Wayne. I assume the box will mount on top of the CreeBar as well as on the dock? I think for some applications it would be nice to have the CreeBar as a heat sink for the power likely to be involved.

Click to expand...

Yes, only the lid where the board is mounted to has holes in it. The box itself is untouched allowing it to be configured in many different ways. The Irakongi box could be mounted to the top of the Cree bar and the Cree bar attached to the Makita Dock putting the driver on the Cree bar.

It may not be the prettiest thing, but, it should be more than functional.

Since both drivers are capable of more power control than before or other drivers the shoppe offered in the past thermal management needs to be taken into account.

Right now there is a single thermistor than can reside on the board or remote mounted to throttle power based on temperature. This is a good first step, but, we actually need to monitor the heat on the driver as well as heat on the heat sink.

In addition, different battery configurations means different parameters. I'm still do not have a complete solution that is simple and easy to configure.

Changing the drive level requires changing the sense resistor. That's ok.

Changing the drive levels for the three settings is controlled by the microprocessor. Right now the settings are fixed. No solution to offer different combinations.

Battery voltage is monitored by the microprocessor. Green - battery good, orange - battery getting low, red - battery critical status is currently setup for the Makita LXT 18V battery. This is something that must be configurable somehow. I would prefer to not offer the change in some menu settings via the microprocessor. I would prefer jumpers, loading resistor combinations or some hardwire method to determine the actual battery status levels.

As it stands now the boost driver works. Depending on how much heat sinking is put on the driver components and PCB will determine how long the driver can run at full power. No heat sinking the driver can run a couple of minutes to continuously with ample heat sinking on components. So, there is a tradeoff of heatsinking to full output duration.

Thinking out loud. It's obvious that there should be ample heat sinking on the PCB eliminating the need to monitor the PCB driver and components. The question arises as to how much time and effort will it take and how much development cost and NRE tooling is required to provide the custom heat sink or find off the shelf heat sinks that will do the job.

Also, It's not even clear at this time what people want or would buy.

Would there be interest in complete solutions? What would that be? Partial solutions like just the driver box.

I can only tell say this. The driver in it's current configuration due to costs in components will not be cheap. The box only adds another $12.00 or so to the price. I would estimate it around $100.00 or so for the assembled box.

Add the Makita dock, loc-line, dual PRCAN and two high powered LED like P7 or two Ostars will add another $60.00 for the LEDs and $120.00 in loc-line parts and head components. That's $280.00 for a complete solution.

For the Cree Bar costs would be approximately $100.00 for the box, $50 for the Cree bar and Cree kit, $12.00 for the Makita Dock and LEDs of choice. That's $162.00 + LEDs.

There is still a lot of development that needs to go into the driver boards to complete the remaining tasks and solve the remaining issues. By far we are still in the early proto phase and things are still evolving. Expressing your interest or desires or suggestion will help drive this project forward.

This project at this point is complete for me. I'm done. I have too many of the Makita lights and configurations that I no longer have desire to build more. Thus, if you would like to see a product come to fruition a lot of you need to come forth, express interest or I will move on since I no longer have any need to build more for myself. I've completed my hobby phase needs.

Let me explain my hobby. I love tinkering making electronic stuff. My goal is to build something that interests me once. When I complete it and am happy with the results I toss it in the "completed" box and move on to the next new electronics project.

To bring something to production sometimes requires more security, safety, user friendliness, mechanical fit and function and most importantly documentation. Sometimes bringing something to production requires tooling, molding which are all one time costs (NRE) and can get very expensive very quick especially if one makes a mistake and has to repeat this costs over more than once.

Wayne

Instead of my expectation and frustations associated with taking a product to production I have thought of another method to offer this to CPF.

What I can do is make a board and test it. Once it is functional I can then offer it in this thread or a dedicated sales thread.

The first person that says I'll take it or something to that effect has first dibs on final configuration and of course it would be customized to his/her preferences. The box will be the base price and any additionals will be incrementally added on. I would like to keep the discussion of final product configuration in the thread to help others in configuration and pricing.

That could be a full completed light with LEDs and battery for example or just the box with driver included.

Since there are several version of the drivers already it could be hard to determine what is what.

I will try to explain as best as possible the board being offered, what it has and what it can do or can't do.

The first person that takes has the option to opt out considering the possible options that he/she may want and I may not be able to accomdate it at that time or the board doesn't have the desired features. It's not a hard sales thread. Only a means to connect product to consumer.

My next post will be the first board to be offered and it will contain the details of the board functionality.

O, since there will be customization and a lot of testing for each configuration custom changes will be accomdated if possible. That includes different battery voltage level states, and max drive current set by the sense resistor.

Wayne

Love it.

But rather than just the two holes for mounting loc-line for two light stalks, I was thinking some kind of common detachable connector like a circular amphenol or something. So that way you could use the Irakongi with Makita Dock as a modular "platform" power base station that you could swap different light/emitter arrays.

Example, you could hook up Don's ultra effecient string of Nichia's in series as one set up. Then unplug it, and put a powerhouse, battery sucking P7 array.

Could be the ultimate transportable work light system.

Just my thoughts.
-Ed

Edwood said:

Love it.

But rather than just the two holes for mounting loc-line for two light stalks, I was thinking some kind of common detachable connector like a circular amphenol or something. So that way you could use the Irakongi with Makita Dock as a modular "platform" power base station that you could swap different light/emitter arrays.

Example, you could hook up Don's ultra effecient string of Nichia's in series as one set up. Then unplug it, and put a powerhouse, battery sucking P7 array.

Could be the ultimate transportable work light system.

Just my thoughts.
-Ed

Click to expand...

Even though the top of the box has two holes for loc-line or exit ports. The base is undefined and could have exit ports on any sides or back allowing as you say an connector, cable or other entry/exit schemes. It's flexible in regards to configuration. If you don't use the two top holes they can always be filled in, capped or left as part of the decoration.

If I understand what you said may not work. The idea is correct, but, a string of Nichias driven at 350mA max is a different driver than one that puts out 3A max. Unless the Nichias were a many strings of Nichias in parallel such that the total current is 3A and each string received 350mA for example. That would work. It wouldn't work if there was one string if Nichias on one cable and one series string of P7s on another unless we added smart cabling sensing and altered the max drive level based on the cable plugged in. Jumpering spare unused pins is a common way to provide electronic identification of what cable is plugged in and based on the cable type alter the drive current accordingly.

Another simple cable identification is to put a resistor on two unused pins and let the microprocessor read the resistor. Use unique and different resistor values for different cable types. One resistor could be for 250mA max drive, another 350mA, another 1A, and another for 3A max drive.

The boxes came in yesterday. Here's a picture of what one looks like.


As you can see the right side is the lower box and is stock with no holes or definition at the moment. The right may look deceptive. It's flat. There is a ridge slot defining the perimeter and it makes the inside portion look recessed. It is flat and not recessed.

Wayne

A couple more pictures of the top lid loaded.





Wayne

dat2zip said:

Even though the top of the box has two holes for loc-line or exit ports. The base is undefined and could have exit ports on any sides or back allowing as you say an connector, cable or other entry/exit schemes. It's flexible in regards to configuration. If you don't use the two top holes they can always be filled in, capped or left as part of the decoration.

If I understand what you said may not work. The idea is correct, but, a string of Nichias driven at 350mA max is a different driver than one that puts out 3A max. Unless the Nichias were a many strings of Nichias in parallel such that the total current is 3A and each string received 350mA for example. That would work. It wouldn't work if there was one string if Nichias on one cable and one series string of P7s on another unless we added smart cabling sensing and altered the max drive level based on the cable plugged in. Jumpering spare unused pins is a common way to provide electronic identification of what cable is plugged in and based on the cable type alter the drive current accordingly.

Another simple cable identification is to put a resistor on two unused pins and let the microprocessor read the resistor. Use unique and different resistor values for different cable types. One resistor could be for 250mA max drive, another 350mA, another 1A, and another for 3A max drive.

The boxes came in yesterday. Here's a picture of what one looks like.
http://i221.photobucket.com/albums/dd291/dat2zip/makita_tri/irakongi_box.jpg

As you can see the right side is the lower box and is stock with no holes or definition at the moment. The right may look deceptive. It's flat. There is a ridge slot defining the perimeter and it makes the inside portion look recessed. It is flat and not recessed.

Wayne

Click to expand...

Ah, so the Irakongi has a fixed current drive output? I guess incorporating resistors into the different cables could work.

Although, I was thinking perhaps having two different light arrays installed, perhaps pulling the same current each, and a Dual Throw 2 Pole switch wired from the Irakongi output. That would let me switch between two different light types, perhaps installed on the same Irakongi base. I'm thinking super flood P4 array (or Cree) and a reflectored P7 array. So I could have both types on it, and I can pick whichever I need. The whole thing is going to be pretty large anyways, might as well, just have it all attached permanently. Could be the ultimate portable shop/work light.

-Ed

You mean something like




Wayne

Just a general status update.

While many of the pieces are in place the drivers are far from being finished even though I have working prototypes. A detailed mechanical/thermal design ensues for proper continuous operation.

I have most of the logistics worked out on the boost driver which I am focusing on first. Currently I am able to drive 6 Crees at 2A from a 9V power supply. Input supply current draw is ~4.2A under these conditions and the board is stable on the open bench. Additional heat transfer is required to keep the driver happy if enclosed.

I have a 200W power supply on order and will be making a test load of 20 Lux3s for a load greater than 50W. The next prototype will have the changes I have worked out for better thermal management and the total power the driver can handle should go up.

The changes and discoveries I find on the boost converter will be applied to the buck design when that comes up.

I am still looking at the logistics of fitting this into a small round board.

Wayne

Wayne, if that driver with work with the Milwaukee V28 Li-Ion pack, I'll buy one. What do you think?

add the dock, loc-line, dual PRCAN and two high powered LED like P7

Click to expand...

I'll take it if you can configure like that for the V28 battery. Sounds like a total of $280?

Just an quick update.

This driver has been my primary focus now for some time. I'm still investigation options, configurations and what the final form factor will be.

One of the investigations was to determine how much power I could drive with the new driver IC I've been working with and did some calculations and determined that with some changes I should be able to hit the 100W mark.

So......

Success! The picture below shows three angle bars upside down. Each angle bracket has 11 Lux3s mounted to them and being driving from the driver. The three strings of 11 LEDs makes 33 LEDs and the drive current is ~850mA to each string ~2.5A out at ~38V Vf. You can read the input power supply voltage and current. Supply was set to 30V.



Here's a picture of the three angle brackets.


Wayne

precisionworks said:

Wayne, if that driver with work with the Milwaukee V28 Li-Ion pack, I'll buy one. What do you think?

I'll take it if you can configure like that for the V28 battery. Sounds like a total of $280?

Click to expand...

Sorry, I just noticed this.

I'll have to test that configuration. What output current would you like and what would the load be?

Wayne

Found this thread. :thumbsup:
I'm looking at powering 7 x Seoul P7 by 8 x 18650 LiIon batteries using a buck configuraton. This will be in a over sized M@glite head. LED's and batteries will be in a series configuration. Current to the emitters at < 3 amps. Board should fit behind the heatsink.

starfiretoo said:

Found this thread. :thumbsup:
I'm looking at powering 7 x Seoul P7 by 8 x 18650 LiIon batteries using a buck configuraton. This will be in a over sized M@glite head. LED's and batteries will be in a series configuration. Current to the emitters at < 3 amps. Board should fit behind the heatsink.

Click to expand...

I am not aware of any driver that will handle the required 73W of power in that small of a footprint. Not on a single board. Maybe, two boards could be made to accommodate that.

Once you get past 25W the laws of physics and todays electronics will force the board size to nearly double. For a single pcb that usually means something larger than the the Mag inner tube diameter.

I would need to know the physical volume behind the heat sink to determine if I could fit the 100W driver I have in there. Note: I don't have a prototype in that size. The current board was designed around the box for the Makita battery pack.

You could use multiple drivers each one driving several LEDs each. That would reduce the requirements per driver and maybe multiple Shark bucks could do the job.

Wayne

An update to this thread.

I made a Makita box with two Shark Bucks (1A), cobbled up base board from a Irakongi LT3478. Using two Nuventix active heatsinks SynJet MR16 style I machined the white adaptor to convert the active heatsinks to locline. I only have one picture of the components for the two heads. The completed assembly was shipped off to attend the PF get together. You can find more info on these neat active heatsinks at www.nuventix.com and this document.



Wayne