The below question is for Aerius Technology in Los Angeles CA.
I am currently attempting to design a power supply to drive a high powered Near Infrared Laser Diode. Right now using the Linear LT3741 which I cannot get to work.
Here are the specifications:
Constant Current, pulsed. Rise time <50us. 0à5A, (0à10A would be great!)
Vin: 12-24V
Vout: 2à6V with an adjustable upper limit (so as not to damage very expensive Laser Diodes.)
Can you please provide a part recommendation that would be a good fit for this application?
Thanks
With the fast rise times and short pulse widths associated with a laser diode, you might consider driving the diode with a MOSFET that can turn on and off quickly. You would use a current sense resitor and monitor it's voltage with a circuit that properly drives the MOSFET to achive the desired forward current. TI has many power solutions to provide a 24V to 6V output at 5A. Power Quick search at http://focus.ti.com/analog/docs/powerhome.tsp?familyId=64&contentType=4&DCMP=TIHomeTracking&HQS=Other+OT+home_p_power will show you the choices. Also note that if your duty cycle ratio of on time to off time is not 100%, the average current from the power supply will not need to be 5A. For example, if you are turning your diode on at a 10% duty cycle, you only need a 500mA power supply. You may be able to design a constant current power supply that meets the tranisent requirements. The TPS40211 might be a good place to start.