System and method for reducing temperature variation during burn in
View Patent ↗Systems and methods for reducing temperature variation during burn-in testing. In one embodiment, power consumed by an integrated circuit under test is measured. An ambient temperature associated with the integrated circuit is measured. A desired junction temperature of the integrated circuit is achieved by adjusting a body bias voltage of the integrated circuit. By controlling temperature of individual integrated circuits, temperature variation during burn-in testing can be reduced.
1. A method of controlling power consumption of an integrated circuit under test during burn-in testing, said method comprising:
determining a junction temperature of said integrated circuit under test;
applying a body bias voltage to a well of said integrated circuit under test; and
adjusting said body bias voltage of said integrated circuit under test to change said junction temperature to achieve a desired junction temperature of said integrated circuit under test.
2. The method of claim 1 wherein said determining said junction temperature comprises:
measuring power consumed by said integrated circuit under test;
measuring an ambient temperature associated with said integrated circuit under test; and
determining said junction temperature by using at least said measured ambient temperature, said measured power, and a thermal resistance value.
3. The method of claim 2 wherein said ambient temperature is measured for a region comprising only said integrated circuit under test.
4. The method of claim 2 wherein said ambient temperature is measured for a region comprising more than one integrated circuit under test.
5. The method of claim 2 wherein said measuring power comprises measuring current supplied to said integrated circuit under test.
6. The method of claim 2 wherein said measuring power comprises measuring voltage supplied to said integrated circuit under test.
7. The method of claim 2 wherein an operating voltage of said integrated circuit under test remains fixed during said measuring, said applying, and said adjusting.
8. The method of claim 1 wherein said body bias voltage is individually controllable for said integrated circuit under test.
9. The method of claim 1 wherein said integrated circuit under test comprises body-biasing well structures to accept said body bias voltage, and wherein said body-biasing well structures are coupled to said well.
10. An apparatus for testing an integrated circuit comprising:
a power measuring device for coupling to said integrated circuit and for measuring power consumption of said integrated circuit;
a body bias voltage supply for coupling to said integrated circuit and for providing a body bias voltage to a well of said integrated circuit;
an ambient temperature sensor for determining an ambient temperature for a region proximate to said integrated circuit; and
a test controller for coupling to said integrated circuit, said power measuring device, said body bias voltage supply, and said ambient temperature sensor, wherein said test controller determines a junction temperature of said integrated circuit by using at least said measured power consumption, said measured ambient temperature, and a thermal resistance value, and wherein said test controller causes adjustment of said body bias voltage to change said junction temperature to achieve a desired junction temperature.
11. The apparatus of claim 10 wherein said ambient temperature is measured for a region comprising only said integrated circuit.
12. The apparatus of claim 10 wherein said ambient temperature is measured for a region comprising more than one integrated circuit under test.
13. The apparatus of claim 10 wherein said body bias voltage is individually controllable for said integrated circuit.
14. The apparatus of claim 10 wherein said integrated circuit comprises body-biasing well structures to accept said body bias voltage, and wherein said body-biasing well structures are coupled to said well.
15. The apparatus of claim 10 wherein said power measuring device comprises a current measuring device.