Ok, but read on, got more info from him on this;
Quote:
The 0.1 Ohm variant was initially done to support 808nm diodes and the driver was run from a 3.3V supply.
Using a 5V supply and a driver with R12 fitted as 0.1R might be ok for 2A through a 445 but there is very little voltage left across the output transistor.
Based on some testing on Photonlexicon the highest Vf for a 445nm diode at 1.53A was 4.99V
(see post 51 in
445nm diode info)
Another diode from an A140 was 4.45V at 1.57A.
At 2A you will have 200mV across the 0.1R
With a 5.0V supply - 0.2V = 4.8V ie less than the Vf at 1.53A
Also you really want a few hundred mV of margin left as Vds on the output MOSFET.
Short answer is it might work for one diode than not work for the next.
If you could push the supply up a little it would be possible for all diodes.
Having a 1R instead of 0.1R also helps with reducing transient susceptibility
End Quote