Protection of an Integrated Circuit and Method Thereof

• US 20080208513A1
• Filed: 04/13/2005
• Published: 08/28/2008
• Est. Priority Date: 04/13/2005
• Status: Active Grant

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Turpin, Pierre, Guillot, Laurent, Dupuy, Philippe, Moreau, Eric
• Granted Patent: US 7,680,622 B2
• Time in Patent Office: Days
• US Class Current: 702/132
• CPC Class Codes: H01L 23/34 Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements thermal treatment apparatus H01L21/00
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An integrated circuit comprises a power device located on a die. The power device is operably coupled to a processing function, wherein the signal processing function is operably coupled to two or more temperature sensors. A first temperature sensor is operably coupled to the power device to measure a temperature of the power device and the second temperature sensor is located, such that it measures a substantially ambient temperature related to the die. The signal processing function determines the temperature gradient therebetween.

In this manner, improved reliability of the integrated circuit and power device is obtained, as the power device utilises the fact that its thermo-mechanical stress reliability strongly depends upon the temperature gradient across the die rather than the number of times it reaches an excessive temperature.

Claims

1. An integrated circuit comprising:

a power device located on a die and a processing function operably coupled to the power device, wherein the processing function is operably coupled to two or more temperature sensors wherein a first temperature sensor is operably coupled to the power device to measure a temperature of the power device and the second temperature sensor is located such that it measures a substantially ambient temperature related to the die and the processing function determines the temperature gradient therebetween.

2. An integrated circuit according to claim 1 further characterised in that the processing function is a digital circuit and in response to the digital circuit determining the temperature gradient between the power device and an ambient temperature, the digital circuit implements a protection process to protect the power device.

3. An integrated circuit according to claim 2 further characterised in that the processing function is operably coupled to a logic gate driver and the protection process comprises switching off the power device by the logic gate driver or reducing the power applied thereto.

4. An integrated circuit according to claim 1, further comprising a counter, operably coupled to the processing function and arranged to count a number of times that the calculated temperature gradient exceeds a threshold value.

5. An integrated circuit according to claim 1, further characterised in that the second temperature sensor is operably coupled to a non-high power device or die.

6. An integrated circuit according to claim 1, further characterised in that the non-high power device or die is a control die, for example in a dual die arrangement.

7. An integrated circuit according to claim 1, further characterised in that the power device is a silicon switch.

11. An integrated circuit according to claim 2, further comprising a counter, operably coupled to the processing function and arranged to count a number of times that the calculated temperature gradient exceeds a threshold value.

12. An integrated circuit according to claim 3, further comprising a counter, operably coupled to the processing function and arranged to count a number of times that the calculated temperature gradient exceeds a threshold value.

13. An integrated circuit according to claim 2, further characterised in that the second temperature sensor is operably coupled to a non-high power device or die.

14. An integrated circuit according to claim 3, further characterised in that the second temperature sensor is operably coupled to a non-high power device or die.

15. An integrated circuit according to claim 4, further characterised in that the second temperature sensor is operably coupled to a non-high power device or die.

8. A method of improving a reliability of an integrated circuit comprising a power device, the method comprising the step of:

measuring a first temperature of the power device;

measuring a second ambient temperature associated with the power device;

calculating a temperature gradient across a portion of the power device in response to the step of measuring;

determining whether the calculated temperature gradient has exceeded a threshold; and

implementing a power reduction process applied to the power device if the temperature gradient exceeds a threshold.

9. A method according to claim 8 further characterised in that the step of measuring a second ambient temperature associated with the power device comprises measuring an ambient temperature of an associated non-high power die, such as an associated control die;

and the step of calculating comprises calculating a temperature gradient between the power die and the non-high power die.

10. A method according to claim 8 further comprising:

incrementing a counter if the temperature gradient exceeded a threshold;

determining whether the Counter has exceeded a threshold;

implementing a power reduction process applied to the power device if the Counter exceeded a threshold.

16. A method according to claim 9, further comprising:

incrementing a counter if the temperature gradient exceeded a threshold;

determining whether the Counter has exceeded a threshold;

implementing a power reduction process applied to the power device if the Counter exceeded a threshold.