High Current Laser Diode Driver Ic

As a result i built this circuit which provides highly accurate current control.

High current laser diode driver ic.

Analog devices laser diode driver ics work with fabry perot dfb and vcsels and the ics support continuous mode data rates from 50 mbps to 11 3 gbps. 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. For the driving of the laser diodes ld special drivers circuits are used. Wavelength electronics has an excellent video describing their current source designs.

Laser diodes are harmful and should have some sort of constant current circuit as a basic protection for the laser diode. 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. 2 produce constant current driven through the ld load.

Laser light amplification by stimulated emission of radiation and laser diodes are widely used in different domain applications it gives focused light ray in visible spectrum and laser diodes will perform good in regulated constant current. 1 produce constant regulated voltage. Laser diode is driven by the open collector output of npn transistor inside elm185xb. In this project we are going to design a simple laser diode driver circuit using an lm317t voltage regulator ic.

This laser diode driver will provide up to 2 5 amps of constant regulated and protected current to the diode. It is good information in block diagram form and easy to understand. Too much current and the laser diode will blow. They can work in two ways.

Too little current and the laser diode will not have sufficient power to turn on and operate. Working of laser diode driver circuit. Therefore drive current max 18v higher than power voltage of ic can be added as drive voltage of laser diode. 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.

The next step is understanding from a schematic point of view how a typical laser diode current source works. Lm317 is a three terminal voltage regulator ic with a high output current value of 1 5a. Quick look at a laser driver circuit. In this project laser diode driver circuit is developed.

The potentiometer 10k and resistor are used as the voltage limiting circuit connected with the adjustable pin1. The module is a great tool to drive low cost laser diodes with superb accuracy. Depends on application laser chosen at different range nm nano meter wavelength and watts. This circuit can drive diode starting from 0 ma to 115ma.

The second type is more easy to design and us.