Actually I had planned on using the stars to get low mode only and then do the testing. But now I don’t have that option and I’ve got to order the new programmer… Assuming it can be. I haven’t even looked at the chip. Still trying to chase down why the other driver doesn’t lower the current after 10 ohms.
105D can be reprogramed, I know because I ordered 5 x 105 C –8 AMC chips and 5 x 105 C6 AMC chips and instead I received 9 x 105 D 8 AMC chips and 1 x 105 D - 6 AMC chips…
Stars are great soldering points if you use firmware for electronic switch which is what I neede them for I can still use them with electronic switch but it is a realy realy PITA to solder wires directly to MCU.
Yep. I’m looking for a corny regulated driver with a sense resister that I calculated around 20 ohms. It isn’t working. So I’ve a new one now to figure out.
Just extra trouble I didn’t need in this job market.
It seems that you are seriously misunderstanding something or multiple things.
None of the drivers being discussed here would ever do what you want. If you purchased a 105c for accurate 1mA output you made a mistake. This is not the thread you are looking for.
What driver did you attempt to use first? 20 ohms suggests an extremely low sense voltage!
I question the need for an accurate 1mA supply for an LED What could you possibly be doing? It seems odd is what I’m saying! Why won’t a very rough, approximate, 1mA be good enough?
Is an accurate 1mA really that difficult? There are many multi-channel LED driver ICs intended for that range. Surely some of them must have tight enough regulation for your purpose?
Also take a look at the first link under WIP in my sig, “17mm double-sided & 20mm+ single sided 4Amp+ linear driver [A17LDX]”. I suspect that this may do what you need.
I bought, paid for, and planned on modifying a 105c. I received something very different in the mail but didn’t realize it because I wasn’t in a position to work on it. Instead I got a D version with some pretty different characteristics.
Since it was my backup plan, I wasn’t too concerned until this thread showed there was an E version with a different MCU.
You see budget FLASHLIGHT but I’m intending the use for another effort. Yes I can get access to ICs that have lower currents but they require a PCB and fab time.
As for the precision… I realize the number of lumens or photons emitted might seem imprudently emphasized. What I work with for prototyping it’s very important.
My apologies for the chime in for an item I did not order.
I understand that you didn’t get what you ordered. The lack of Google hits for 105d was part of why I saw fit to start this thread. That wasn’t really my point though.
What I was getting at was more along the lines of “why don’t you spill the beans and maybe we’ll help you do what you at trying to do” since it seems that your efforts so far have been pretty far off base. You also specifically said flashlights in your first post. Come to think of it, you also said 10mA, then later said 1mA? You’re still welcome to spill the beans and get help.
Error some of that is android and it’s wonderful auto correct.
There isn’t really beans to spill. I work with photometrically sensitive films. The can’t have any sort of exposure and they can only tolerate certain wavelengths.
So somewhere in the interpolated emission charts 1 to 10 ma would give me the desired photon flux such that a human eye can navigate under night vision but a radiometric sensitive emulsion would not appreciably fog.
Kinda a fun problem I’ve licked in the past.
Can always apply nd filters to the emitter to knock down the flux. Don’t have any ideas yet until we measure how many photos actually will dog the emulsion.
That’s much more engaging as far as I’m concerned. Are the films for scientific purposes?
ND filters makes sense.
What driver did you try earlier?
I do think that the QX7136 is probably a good fit. It sounds like you want single-mode, so in that application it would be completely constant current. You don’t even need an external MOSFET for such a low current, it has an internal one you can use.
No, you are not, but not all films are red insensitive.
That’s mostly due to the type of silver chloride used. Other find that have, say, sensitivity to ir or UV might have different wavelengths of less sensitivity.
For those that were wondering how this ended up, my ultra-low-LED flashlight was considered ‘too bright’ with a 252kohm resistor on it for sensing current. I’ve been meaning to go back and measure the current with a fluke but the last time I tried it didn’t go low enough…. and I’m not taking a flashlight over to the NIST lab for testing.
I couldn’t accurately measure the flux on most instruments. The reflector was causing most of the problems due to the focus of the beam- which was why it was designed that way.
Ugh! I have a need to reflash 4 drivers and convert them to off-time memory with the added capacitor, but when I checked the lights I see they have 105*D* drivers installed! Ugh! I guess my best and easiest option is to replace them with 105*C*’s? Unless someone can point me to a firmware that gives me proper off-time memory without the capacitor. What I am really looking for is to have “off-time memory” on a driver set to “no memory” (it makes mode switching much much easier!). I’m very much a novice with firmware code and flashing, so it would have to be easy for me to modify and reflash (I’m currently only using STAR & STAR Off-Time and only modifying PWM levels for modes).
Hi Garry,
take a look at a relatively new firmware @Toykeeper has written.
It’s named “biscotti”.
Written for the 105D, offtime memory without cap by using brown out detection (BOD). And she crammed in all functionality the 13A with 1 kB can take.
You find it in Toykeepers firmware repository.
Just be sure to use the right fuses, there are reports of bad timing when flashed incorrectly.