Control circuit for optoelectronic module with integrated temperature control
View Patent ↗A microprocessor is used to control the temperature of a laser emitter and thereby regulate the wavelength of optical signals from the laser. A serial interface in the microprocessor provides input and output lines to a host device, and temperature lookup tables are stored in nonvolatile memory. Control logic processes information stored in the memory as well as information on operating conditions of the laser emitter to precisely control the temperature of the laser emitter. A thermo-electric cooler adjusts the temperature of the laser emitter.
1. An optoelectronic assembly, selected from one of an optoelectronic transceiver and an optoelectronic transmitter, comprising:
a housing;
a laser emitter disposed within the housing;
a laser driver disposed within the housing;
a temperature control mechanism disposed within the housing for regulating temperature of the laser emitter;
an integrated circuit disposed within the housing configured to set at least one operating parameter for the temperature control mechanism and further configured to provide a control signal to the laser driver;
a receiver optical subassembly; and
a post-amplifier configured to provide a feedback signal to the integrated circuit, the feedback signal providing a signal detect output to the integrated circuit.
2. The optoelectronic assembly of claim 1 , wherein the temperature control mechanism comprises:
a thermo-electric cooler configured to regulate the temperature of the laser emitter; and
a thermo-electric cooler driver configured to drive the thermo-electric cooler.
3. The optoelectronic assembly of claim 2 , wherein the temperature control mechanism further comprises a thermo-electric cooler controller configured to control the thermo-electric cooler driver.
4. The optoelectronic assembly of claim 1 , further comprising a sensor disposed within the housing configured to detect an operating condition of the laser emitter, wherein the temperature control mechanism is configured to cause the operating condition to attain a target operating value.
5. The optoelectronic assembly of claim 4 , wherein the operating condition is the temperature of the laser emitter.
6. The optoelectronic assembly of claim 1 , further comprising a laser driver disposed within the housing and configured to apply a bias current to the laser emitter, wherein the integrated circuit is configured to set at least one operating parameter for the temperature control mechanism based in part on a voltage corresponding to the bias current.
7. The optoelectronic assembly of claim 1 , further comprising an ambient temperature sensor for measuring ambient temperature surrounding the laser emitter, wherein the integrated circuit is configured to set at least one operating parameter for the temperature control mechanism based in part on the ambient temperature.
8. The optoelectronic assembly of claim 1 , wherein the operating parameter is a reference voltage.
9. The optoelectronic assembly of claim 1 , wherein the integrated circuit comprises:
memory, including one or more memory arrays for storing information related to the laser emitter;
an interface for reading digital values from and writing digital values to locations within the memory in accordance with commands from a host device;
analog to digital conversion circuitry for receiving a plurality of analog signals, converting the received analog signals into digital values, and storing the digital values in predefined locations within the memory; and
control circuitry configured to generate control signals to control operation of the laser emitter in accordance with one or more digital values stored in the memory.
10. The optoelectronic assembly of claim 9 , wherein the memory includes a lookup table having a plurality of entries, and the integrated circuit is configured to set at least one operating parameter for the temperature control mechanism based in part on one of the plurality of entries in the lookup table.
11. The optoelectronic assembly of claim 1 , wherein the integrated circuit is further configured to measure an input optical power received by the receiver optical subassembly.
12. The optoelectronic assembly of claim 1 , wherein the integrated circuit is further configured to perform a setup-function of the optoelectronic assembly.
13. The optoelectronic assembly of claim 1 , wherein the integrated circuit is further configured to store an identity code within a general purpose memory.
14. The optoelectronic assembly of claim 1 , wherein the integrated circuit is further configured to control an output optical power level of the laser emitter.
15. The optoelectronic assembly of claim 1 , wherein the integrated circuit is further configured to determine a reference voltage value associated with a target temperature for the laser emitter based at least in part on an ambient temperature of the optoelectronic assembly and one or more entries in a lookup table in a memory of the integrated circuit.
16. An optoelectronic assembly, selected from one of an optoelectronic transceiver and an optoelectronic transmitter, comprising:
a housing:
a laser emitter disposed within the housing;
a laser driver disposed within the housing;
a temperature control mechanism disposed within the housing for regulating temperature of the laser emitter; and
an integrated circuit disposed within the housing configured to set at least one operating parameter for the temperature control mechanism and further configured to provide a control signal to the laser driver, wherein the integrated circuit includes a proportional integral differential controller configured to generate a pulse width modulated signal having a pulse width corresponding to the temperature control value.
17. The optoelectronic assembly of claim 16 , further comprising a filter coupled to the integrated circuit and configured to filter the pulse width modulated signal and provide the filtered pulse width modulated signal to the temperature control mechanism.
18. The optoelectronic assembly of claim 1 , wherein the temperature control mechanism is integrated within a laser transistor-outline (TO) package.