AX2002 lowest output

[Zeebit]

I would like to use the DX buck driver for an Opnext 638nm diode. I've taken a look at the datasheet and the lowest output current I've seen is 300mA. Can this chip go any lower?

I would like to test it myself but I do not have the proper equipment for testing for stability.

 

[foulmist]

I am pretty sure it can. Just use the following formula

R = V / I

replace the sense resistor with the closest value you get and you are good to go. Those ICs are pretty stable and decent!

 

[JLSE]

I run lower power diodes at 150mA with no problem. The relationship between input and output voltage
can cause issues, but other than that, providing lower current has been no issue for me.

*edit Just be careful with diodes that have active ground pins, especially -neg gnd...

 

[Zeebit]

Can you explain the relationship between Vi and Vo more?

 

[JLSE]

Just be careful when your input voltage is low, as in, use with 2 Li-ion's in series, no matter
how low the vf of the diode. A fully charged li-ion is ~4.2v, but once it drops down around the
3.6v mark, you can blow your diode as they become unstable at this voltage.

With 445's its not much of an issue, but with reds and IR you still have to keep well above the 3.6v mark or
the driver can dump extra current on the load. I just blew a single mode 635nm LD because of it :cryyy:
MY bench supply was at a low voltage by mistake, and p00f!

AX2002 based drivers work best at 8-12v, I have had no issues keeping with that. The current, you can
set it plenty low :beer:

 

[Zeebit]

Okay man. Thanks for helping out! :beer:

Rep when I can