ELM185xBLaser Diode Driver

ELM185xB is a bipolar type laser diode driver IC with internal APC circuit which consists of a reference voltage source, an error amplifier, and a thermal shutdown circuit for protection. With reference voltage source, the output of laser is comparatively stable during the change of power voltage and temperature. With its small package, ELM185xB is possible to be assembled within small areas on the board. When control loop damage occurs, ELM185xB is also capable of limiting the laser drive current; limited current value can be adjusted by an external resister on ILM. KLD output drive current can reach up to 400mA (max.). For avoidance of damage of laser diode, the Zener diode which is included in ELM185xB is able to absorb 8V surge between VCC-GND. ELM185xB is able to drive various types of laser diode modules (LDM); please refer to applicable laser diode modules for further information. ELM185xB can not only drive laser diode by APC control, but also by constant current with internal constant current setup function; therefore, ELM185xB can also be used as constant current driver for laser diode, high luminous LED, etc.

Low voltage operation2.0V
Low current consumption operationTyp.1mA
Laser drive current Max.400mA
Internal voltage referenceTyp.0.30V
Thermal shutdown circuitTyp.150°C
Zener diode for surge absorption included
  • (* For SQP (Small Quantity Purchase)customers Sample
    available: buyer need to pay the sample fee and delivery
    fee. For more information, please contact
    ★ elm-tech.com.(Please change ★ to @.))
Driver for laser diode in laser pointer, laser level, etc.
Driver for constant load current such as LED, etc.

Absolute Maximum Ratings

Operation voltageVCCGND-0.3 to 7.0V
CMP voltageVcmpGND-0.3 to 7.0V
ILM voltageVilmGND-0.3 to 7.0V
KLD voltageVkldGND-0.3 to 18.0V
AMD voltageVamdGND-0.3 to VCC+0.3V
KLD currentIkld500mA
Power dissipationPd300(SOT-26), 1000(WSON6-2x2)mW
Operating temperatureTop-30 to +85°C
Storage temperatureTstg-40 to +125°C

Block diagram