Koheron DRV200 User manual

Quickstart
1 Turn the setpoint potentiometer counter-clockwise to set the current to 0 mA.
2 Connect the pins VCC and GND to a 5 V power supply. Thanks to the very high power
supply rejection of the DRV200, a switched power supply can be used without degrading
the noise performance. However, the current limit functionality of lab power supplies can
be useful.
3 (Optional) Connect a 1 Ωresistor between the LD+ and LD- pins. The current flowing
across the resistor can be measured at the IMON pin (2 V = 100 mA for DRV200-A-200,
100 mV = 1 mA for DRV200-A-40). Turn the potentiometer clockwise until you reach the
desired current.
4 Turn off the power supply and connect your laser between LD+ and LD- pins.
The DRV200 is designed for operation with floating laser diodes, i.e. that neither the
anode nor the cathode is connected to the case. If your laser anode or cathode is
internally connected to the case (grounded anode or grounded cathode), make sure that
the laser case is isolated from the ground.
5 Turn on the power supply and adjust the potentiometer

Current modulation
The DRV200 can be modulated from DC to 5 MHz using the SMA connector. A jumper
is used to select between 3 modulation gains:
DRV200-A-40
gain 1 : 200 µ/V
gain 10: 2 mA/V
gain 100: 200 mA/V
DRV200-A-200
gain 1 : 1 mA/V
gain 10: 10 mA/V
gain 100: 100 mA/V
Modulation range is +/-1 V and input impedance is 50 Ω.
The modulation transfer function is shown below: