Microcontroller based thermoelectric cooler controller
Controlling a thermo electric cooler (TEC) in a transceiver using a microcontroller. The microcontroller is used to control functionality in addition to the TEC control functionality. Specifically, the TEC is controlled using a control algorithm in the microcontroller. The microcontroller sends signals to a switching device that controls current through TEC.
1 . An apparatus for controlling a TEC comprising:
a switch device, the switch device adapted supply current to a TEC;
a microcontroller coupled to the switch device, the microcontroller configured to control the switch device to allow current flow through a TEC and to control other transceiver module functionality in an optical transceiver.
2 . The apparatus of claim 1 wherein the switch device is adapted to switch current in a first and a second direction for switching the sides of a TEC that are heated and cooled.
3 . The apparatus of claim 2 wherein the switch device comprises an H bridge.
4 . The apparatus in claim 1 wherein the switch device is a class D amplifier.
5 . The apparatus of claim 1 wherein the microcontroller is configured to implement a different feedback control at start up of a transceiver than during a steady state control.
6 . The apparatus of claim 1 wherein the microcontroller is configured to implement a feedback control that uses a parameter defining the age of a light generating device.
7 . A transceiver for use in fiber-optic communications the transceiver comprising:
a light generating device configured to convert electrical signals to optical signals for transmission on a fiber-optic network;
a TEC coupled to the light generating device and configured to regulate the temperature of the light generating device;
a switch device coupled to the TEC, the switch device configured to switch current through the TEC; and
a microcontroller coupled to the switch device wherein the microcontroller is configured to control the switch device, the microcontroller also being configured to control functionality of at least one other function or device in the transceiver.
8 . The transceiver of claim 7 , wherein the light generating device is an LED.
9 . The transceiver of claim 7 , wherein the light generating device is a laser diode.
10 . The transceiver of claim 7 , further comprising a heatsink coupled to the TEC.
11 . A method of controlling temperature of components on a transceiver, the method comprising:
sensing temperature of a device in the transceiver;
providing an indication of temperature of the device to a microcontroller;
at the microcontroller performing a control algorithm using the indication of temperature as a feedback parameter, wherein the microcontroller performs other functionality in the transceiver;
sending a control signal to a switching device, the control signal being dependant on the results of performing a control algorithm; and
at the switching device, switching a current to a TEC such that the thermal response of the TEC to the current can be used to regulate the temperature of the device in the transceiver.
12 . The method of claim 11 , wherein switching a current to a TEC causes a first side of the TEC connected to the device in the transceiver to be cooled.
13 . The method of claim 11 , wherein switching a current to a TEC causes a first side of the TEC connected to the device in the transceiver to be heated.
14 . The method of claim 11 , wherein switching a current to a TEC comprises switching a pulse width modulated current to the TEC such that when the pulse width modulated signal is high, one side of the TEC is heated and when the pulse width modulated signal is low, the one side of the TEC is cooled.