Low noise laser diode driver with modulation
Koheron DRV200 drivers are ultra-low noise current drivers combining a very stable current bias with a ±1 V modulation input from DC to 5 MHz. Current bias can be set from 0 to 200 mA with a manual potentiometer. A jumper allows to choose between 3 modulation gains.
| Quantity | Price |
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Resources
Specifications
| DRV200-A-40 | DRV200-A-200 | DRV200-A-400 | |
|---|---|---|---|
| Laser current | 0 - 40 mA | 0 - 200 mA | 0 - 400 mA |
| Supply voltage VS | 5 V or 6 V | 5 V or 6 V | 5 V or 6 V |
| Compliance voltage 5V supply | 2.8 V at 50 % current max., 1.8 V at current max. | 2.8 V at 50 % current max., 1.8 V at current max. | 2.8 V at 50 % current max., 1.8 V at current max. |
| Compliance voltage 6V supply | 3.8 V at 50 % current max., 2.8 V at current max. | 3.8 V at 50 % current max., 2.8 V at current max. | 3.8 V at 50 % current max., 2.8 V at current max. |
| 3 db modulation bandwidth | 8 MHz | 6 MHz | 6 MHz |
| Current monitor gain | 100 mV/mA (up to 40 mA) | 20 mV/mA (up to 200 mA) | 10 mV/mA (up to 400 mA) |
| Temperature coefficient | 30 ppm/°C | 30 ppm/°C | 30 ppm/°C |
| RMS noise (10 Hz - 1 MHz) | 65 nArms | 255 nArms | 530 nArms |
| Current noise density (1 kHz) | 55 pA/√Hz | 270 pA/√Hz | 480 pA/√Hz |
| Current limit | 48 mA (ILIM H), 32 mA (ILIM L) | 240 mA (ILIM H), 160 mA (ILIM L) | 480 mA (ILIM H), 320 mA (ILIM L) |
| Slow start (90 % setpoint) | 1.0 s | 1.0 s | 1.0 s |
| Modulation gains | 200 µA/V, 2 mA/V, 20 mA/V | 1 mA/V, 10 mA/V, 100 mA/V | 2 mA/V, 20 mA/V, 200 mA/V |
| Outside Dimensions | 72 mm x 38 mm x 14 mm | 72 mm x 38 mm x 14 mm | 72 mm x 38 mm x 14 mm |
| Compatible lasers | Floating diodes | Floating diodes | Floating diodes |
Characterization
Current noise
The figure below shows the current noise of the different DRV200 laser driver variants operated at a maximum rated current:
Current noise was measured across a 30 Ω resistor for the 40 mA laser current version (A-40) and a 5 Ω resistor for the 200 mA laser current version (A-200) and for the 400 mA laser current version (A-400).
Current stability
The figure below shows the current evolution of the 200 mA laser current version driver (A-200) delivering 200 mA over 40 hours. The ambient temperature is 25 °C. Current is measured using a 5 Ω precision resistor and a 7.5-digit digital voltmeter.
Fluctuation is about 10 ppm per day.
Temperature coefficient
The figure below shows the current variation for different ambient temperatures between 5 and 55 °C. Temperature coefficient is below 30 ppm/°C.
DC current modulation input
The DC modulation input controls the current setpoint. It combines large bandwidth and high linearity.
Modulation performance are characterized using a DFB laser. Large and small signal correspond to a modulation signal of 2 Vpp and 500 mVpp, respectively. The modulation is detected by a 70 MHz DC coupled PD100 photodetector and measured on an oscilloscope.
Revision history
- 2 - July 2018: Add jumpers for selection of current limit (High / Low) and supply voltage (5 V / 6 V).
