Laser current is equal to ISET + ITRIM + IMOD, where:
- ISET is set by the ISET trimmer.
- ITRIM is proportional to the voltage on the TRIM input (2 kΩ impedance, 10 Hz bandwidth).
- IMOD is proportional to the voltage on the MOD IN SMA connector (50 Ω impedance, 10 MHz bandwidth).
Connections
Terminal block
VCC: Supply input. Connect this pin to a 9 V supply.
EN: Laser Enable pin. Apply a voltage between 2.2 V and 4.5 V to enable the laser current.
TRIM: Laser current trimming input with 2 kΩ input impedance, ±2 V input voltage range and 10 Hz bandwidth. DRV300-A-10 gain is 0.5 mA/V. DRV300-A-40 gain is 2 mA/V. DRV300-A-200 gain is 10 mA/V.
IMON: Laser current monitoring pin. The voltage at this pin is proportional to the laser current. DRV300-A-10 current monitor gain is 100 V/A. DRV300-A-40 current monitor gain is 25 V/A. DRV300-A-200 current monitor gain is 5 V/A.
LD+: Laser anode pin. Connect this pin to the laser anode.
GND: Ground. Connect this pin to the laser cathode.
Switch
EN: Enable / disable laser current.
ILIM: Set to ON/OFF for Low/High current limit.
G0, G1: Set modulation gain as follows:
| G0 | G1 | Modulation gain |
|---|---|---|
| OFF | OFF | High (x 1) |
| ON | OFF | Medium (x 1/5) |
| OFF | ON | Low (x 1/25) |
LED
The LED lights up when the laser driver is enabled.
Mounting multiple DRV300 in parallel
To mount the laser drivers in parallel, tie LD+ pins together as follows:
