Patent ID: 6947458

Claim:
A control circuit for a laser diode, the circuit comprising: a power control circuit for controlling an adjustable bias current to the laser diode that includes: a bias current source that provides an adjustable bias current to the laser diode and having a power reference voltage input; a power monitor loop including a backface diode for monitoring the laser diode power output to provide a power monitor signal; a power control signal combined with the power monitor signal to provide a power adjust signal, wherein the bias current source adjusts the bias current responsive to a difference between the power reference voltage input and the power adjust signal; and a temperature control circuit that provides a control current to a thermoelectric element for controlling temperature operation and wavelength of the laser diode that includes: a temperature reference voltage input; a temperature monitor loop including a temperature sensor for monitoring the temperature operation point to provide a temperature monitor signal; a wavelength compensation signal combined with the temperature monitor signal to provide a wavelength control signal, wherein the wavelength compensation signal is proportional to the power control signal; wherein the temperature control circuit adjusts the control current to the thermoelectric element responsive to a difference between the temperature reference voltage input and the wavelength control signal to help maintain operation of the laser diode around a nominal operating wavelength.