Product Brief


  • Low-noise programmable current source up to 1A
  • Integrated TEC controller/driver
  • SPI Interface (includes USB to SPI cable)
  • Software GUI provides computer control
  • Non-volatile storage of bias and temperature setpoints
  • Analog inputs for fine laser temperature and bias control


1.  From digitally programmed temperature setpoint

2.  Corresponds to 0-20uA monitor photodiode photocurrent


The FP4525 Whisper Drive is a stand-alone solution for driving our DFB laser products.  The driver consists of a programmable laser bias current source (1A maximum) as well as a thermoelectric cooler (TEC) controller/driver with programmable temperature setpoint. The FP4525 is computer controlled using the supplied USB to SPI adapter cable and software interface. Bias and temperature setpoints can be stored in non-volatile memory for use without requiring computer control.  The current source and TEC driver are all-linear, low-noise implementations to prevent degradation of laser performance. Analog inputs are provided for fine adjustment of laser setpoints and for customer-implemented closed loop control.  An internal transimpedance amplifier converts the monitor photodiode photocurrent into an analog voltage available on the interface connector.  A power supply is provided.

Product Data Sheet


Laser Bias CurrentFSI0-1A
Laser Bias Current Setpoint Resolution1mA
Laser Temperature SetpointT laser
Laser Temperature Setpoint Resolution0.03°C
TEC Voltage (maximum)
TEC Current (maximum)
Power Adjust Analog Input Voltage
Power Adjust Current Adjustment
Temperature Adjust Analog Input Voltage
Temperature Adjust Magnitude1±4°C
Monitor PD Output Voltage2VMON0-3V
Input Supply Voltage
Input Supply Current (maximum)5.5A