Patent ID: 7646175

Claim:
A device for supplying a current to a load, the device comprising: a temperature detector circuit configured to detect a peripheral temperature of the load and output a detection signal having a high or low value determined by a relation of the peripheral temperature to first and second reference peripheral temperatures, the first reference peripheral temperature being higher than the second reference peripheral temperature; a timing generator circuit connected to the temperature detector circuit and configured to generate a timing signal having a value periodically switched between a high and low value, the timing signal being held at one of the values for a predetermined time when the detection signal indicates the peripheral temperature of the load is higher than the first reference peripheral temperature; a switching circuit comprising inverted AND logic and receiving as inputs the detection and timing signals output by the temperature detector circuit and timing generator circuit, respectively, configured to generate a switch signal having a high or low value determined by the values of the timing signal and the detection signal; and a current supply circuit connected to the switching circuit and configured to supply a high or low value current to the load depending on the value of the switch signal, the low value current being a current value that, when supplied to the load, causes the peripheral temperature of the load to decrease, wherein the switching circuit is operable to cause the current supply circuit to supply the high value current to the load until the detection signal indicates the peripheral temperature of the load is higher than the first reference peripheral temperature; and supply the low value current to the load until both the timing signal indicates the predetermined time has elapsed and the detection signal indicates the peripheral temperature of the load is lower than the second reference peripheral temperature.