1161 Ringwood Ct, #110, San Jose, CA 95131, U. S. A. Tel.: (408) 748-9100, Fax: (408) 770-9187

www.analogtechnologies.com

Copyrights 2000-2022, Analog Technologies, Inc. All Rights Reserved. Updated on 1/17/2022

Email: staff@analogti.com/sales@analogti.com

10

Analog Technologies

Low Noise Constant Current Laser Controller

ATLS500MA103

Driving High Voltage Laser Diodes

Some laser diodes have high forward voltage, such as 7V,

while the laser driver ATLS500MA103D has a maximum

output voltage of 4V. This section tells a way to drive such

laser diodes by using this laser driver.

The schematic is shown in Figure 19, where Power Supply 1

is the power supply for the laser driver, Power Supply 2 is for

increasing the laser driver's maximum output voltage.

Please notice that the power on sequence has to be in this way:

turn on Power Supply 1, turn on Power Supply 2, then turn on

the laser driver by driving SDN (Shutdown) pin to logic high.

The sequence for turning off the laser circuit is: turn off the

SDN pin by pulling it down to the logic low, turn off Power

Supply 1, then, turn off power supply 2.

To make sure the circuit works ok: turn on the laser, measure

LDA voltage, it should be between 1V to 3V, at room

temperature, the ideal LDA voltage is around 2V.

Figure 19. Driving High Voltage Laser Diodes

Figure 20. Output Current vs. LIS and LILM Voltage