High Current Laser Diode Driver Ic

For the driving of the laser diodes ld special drivers circuits are used.

High current laser diode driver ic.

This circuit can drive diode starting from 0 ma to 115ma. As battery start giving supply it first flow through the ceramic capacitor 0 1uf. Elm recommends inserting resistance between laser diode module ldm and kld if the drive voltage is high so as to disperse power loss. Quick look at a laser driver circuit.

The module is a great tool to drive low cost laser diodes with superb accuracy. As a result i built this circuit which provides highly accurate current control. Wavelength electronics has an excellent video describing their current source designs. Too little current and the laser diode will not have sufficient power to turn on and operate.

Configurable current limits with jumpers for 0 5 1 0 1 5 2 0 and 2 5 amp settings and adjustable output with an analog trim pot. 1 produce constant regulated voltage. In this project laser diode driver circuit is developed. 2 produce constant current driven through the ld load.

The second type is more easy to design and us. Depends on application laser chosen at different range nm nano meter wavelength and watts. Featuring dual loop control of extinction ratio and average power our laser diode drivers maintain a preset oma or optical average power output by sensing and processing the laser mpd feedback with. A driver circuit is a circuit which can limit appropriately the amount of current being fed into the laser diode so that it can function correctly.

Working of laser diode driver circuit. Too much current and the laser diode will blow. The next step is understanding from a schematic point of view how a typical laser diode current source works. It is good information in block diagram form and easy to understand.

Laser diodes are harmful and should have some sort of constant current circuit as a basic protection for the laser diode. This capacitor is used to filtering high frequency noise from our dc source and gives to input pin3 of the lm317 voltage regulator ic. The lm317 ic has many features such as current limiting thermal protection and safe operating area protection. In this project we are going to design a simple laser diode driver circuit using an lm317t voltage regulator ic.

The potentiometer 10k and resistor are used as the voltage limiting circuit connected with the adjustable pin1. Therefore drive current max 18v higher than power voltage of ic can be added as drive voltage of laser diode. Lm317 is a three terminal voltage regulator ic with a high output current value of 1 5a. Laser diode is driven by the open collector output of npn transistor inside elm185xb.

This laser diode driver will provide up to 2 5 amps of constant regulated and protected current to the diode.