I want to use a high power laser diode modulated at 40-some kHz. to send “tight beam” IR control signals (like a TV remote control code, for example).
I know there are commercial “TTL” laser controller boards available, but I’ve found none that can switch at 40 kHz or above.
So (please see attached circuit concept) I drew up a little high side switch intended to be run by an Arduino output pin. The switch turns on or off the power to the LM-338 chip (a 5 amp adjustable regulator similar to the LM-317).
The LM-338 is wired as a CONSTANT CURRENT source and the resistor across the output and control pins controls the current. The actual component values are yet TBD… but whatever they are will not change how the circuit works.
So, I would appreciate any comments on the circuit design, can it be improved, etc…