Correct, the H17F is simply a PWM FET driver, unless you can have it setup to limit the max duty to around ~70% it will drive the LED with over 11A. Which is far too much.
If you limit the max duty it works ok, you will just loose around 10-15% output compared to a true constant current driver.
I think up to 3A it is a linear driver. It uses 8x 7135 for that. Only for half turbo and turbo it uses a FET. See Dr. Jones’ description here:
http://drjones.nerdcamp.net/h17f.html
I think it should be fine when using a non performance cell or a current limited power supply while programming in order to protect the LED.
Correct, it will work in the 7135 mode but the turbo modes will drive it at around 11-12A unless the pwm is limited.
Even with a laptop pull I was getting around 8A IIRC which is way over what most laptop cells are rated for and not safe for that reason. With a GA it still gets over 10A.
The only way I have found to run it on an FET is by limiting the PWM. The TA driver works in the same way and that is what I do with it.
Although I hardly ever use turbo, 95% of the time the 7135 mode is enough.
Is there a good cell to use for programming to prevent blowing anything up?
I had this with a single 219B. It melted my first switch. Turned the LED blue during programming but survived. I’d rather limit things though.
As long as the LED is properly reflowed onto a DTP MCPCB and it has a good heat path they can handle a LOT of power. I have yet to kill a 219C. The output just drops massively and it gets really hot. For example it will put out basically the same luemens at 2.45A as in turbo @ 12A.
If you want to play it safe, use a cheap cell that is not fully charged, say around 3.6V.
Good to know the 219c can handle the higher currents without killing it. I believe I read somewhere that the FET used on these drivers top out around 10A, but that could have been in a specific build with other factors. I’ll go see if I can dig up the source.
I think I’ll give this build a go and program with a weaker cell. It will only be on the FET for a short period of time while programming.
That 10A limit would be the max the FET can handle without melting, not the max it can deliver. Although on a single 219C the max would most likely be less then 10A as it will have more resistance then the normal FET’s we use around here.
Ah okay, thanks for the details. Does that mean these drivers shouldn’t be used on quads/triples that can pull a lot more than 10A?
This is what I have in a few of my builds but I rarely use the full turbo mode for extended periods.
That would be a question for the guy selling it (forgot who it was). He will know what the specs on the parts are.
You can be sure that they will pull more then 10A though with a triple or quad 219C.
Currently, they are being sold by MTN. I’ve asked the question in the H17F thread.
On a more on topic note, I finished my s41 quad build with 2x 5000k and 2x 4000k and it does give a more balanced tint. Personally, the 5000k was a bit too cool for me and the 4000k a bit too warm.
This may be a bit subjective since I’m eyeballing it, but it appears there is a bit of green when mixing the 2 different LEDs. I’ll have to use it more, and also try it without the lens to see if anything changes.
Strange, isn’t it?
It’s as if it’s like cool - cool - neutral - neutral - warm - warm, with only slight differences among the 2 of each main colour temperature.
It is what it is. I’m about to post the complete tint shots (minus the 219B 9080) very soon. Still repairing the boost driver I kept for a long time.
To me it looks more like
cool - neutral - warm - warm - warm - warm
perception is individual
BTW, the sm303 and sm273 gets almost the same as the current increase. Also notice the red really pronounced in very low current. This also validate Maukka’s statement somewhere in BLF.
My power supply reached it’s limit at 51,02 watts (52,13 V & 0,98 A)
Got my 219C 353’s in today… I think 3 of them and 1 219C 403 will go into a quad X5. Maybe it will be 2 and 2 not sure yet. Will be driven by a CC LD3 at 12 amps! Going to be a fun Hi CRI build that is for sure.
Hmmm… The 503 and 573 have higher Vf than 403, 353, 303 and 273, don’t they?
So inparallel the ones with lower Vf will draw the most Amperes.
Yes, lower Vf=more amps. I have 1 triple build with 219C’s and it can get into crazy amps if you use a good cell and do bypasses. My hope is to get good performance and maintain control with any battery by using the LD3.
Sorry, i misread your comment, but now i see you want to combine 353 with 403.
(i somehow read / thought you meant 503 :person_facepalming: )
I didn’t have too much play time to test each types separately, hence the non uniform brightness.
Ran them all in series. Different Vf is always a problem especially in ultra low current.