Semiconductor device and method of operating the same

• US 20100308893A1
• Filed: 04/13/2010
• Published: 12/09/2010
• Est. Priority Date: 06/04/2009
• Status: Abandoned Application

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: NEC Electronics Corporation (Renesas Electronics Corporation)
• Inventors: Fukuoka, Atsuhisa
• Application Number:
  US12/662,359
• Publication Number:
  US 20100308893A1
• Time in Patent Office: Days
• US Class Current: 327/512
• CPC Class Codes: H03K 17/14 Modifications for compensating variations of physical values, e.g. of temperature

Abstract

A semiconductor device includes: a high VT part including a first transistor with first threshold voltage; a low VT part including a second transistor with second threshold voltage lower than the first voltage; a temperature detector which measures a temperature of the semiconductor device, determines whether the temperature is in a high temperature state where the temperature is higher than a predetermined temperature or a low temperature state where the temperature is lower than the predetermined temperature, and outputs a signal indicating the high temperature state or the low temperature state; and a controller which receives the signal indicating the high temperature state or the signal indicating the low temperature state, and performs control to cause the high VT part to operate based on the signal indicating the high temperature state and to cause the low VT part to operate based on the signal indicating the low temperature state.

Claims

1. A semiconductor device comprising:

a high VT part including a first transistor with a threshold voltage of a first voltage;

a low VT part including a second transistor with a threshold voltage of a second voltage lower than the first voltage;

a temperature detector which measures a temperature of the semiconductor device, determines whether the temperature is in a high temperature state where the temperature is higher than a predetermined temperature or a low temperature state where the temperature is lower than the predetermined temperature, and outputs a signal indicating the high temperature state or a signal indicating the low temperature state; and

a controller which receives either the signal indicating the high temperature state or the signal indicating the low temperature state, and performs control to cause the high VT part to operate based on the signal indicating the high temperature state and to cause the low VT part to operate based on the signal indicating the low temperature state.

2. The semiconductor device according to claim 1, wherein

the high VT part includes:

a high VT logic circuit including the first transistor; and

a first switch part which switches between ON and OFF of power supply to the high VT logic circuit,

the low VT part includes;

a low VT logic circuit including the second transistor; and

a second switch part which switches between ON and OFF of power supply to the low VT logic circuit,

the controller outputs a first signal to the first switch part on the basis of the signal indicating the high temperature state, and outputs a second signal to the second switch part on the basis of the signal indicating the low temperature state,

the first switch part supplies power to the high VT logic circuit on the basis of the first signal, and

the second switch part supplies power to the low VT logic circuit on the basis of the second signal.

3. A method of operating a semiconductor device comprising the steps of:

measuring a temperature of the semiconductor device;

determining whether the temperature is in a high temperature state where the temperature is higher than a predetermined temperature or a low temperature state where the temperature is lower than the predetermined temperature;

outputting a signal indicating the high temperature state or a signal indicating the low temperature state on the basis of the determination;

receiving the signal indicating the high temperature state or the signal indicating the low temperature state; and

operating a high VT part including a first transistor with a threshold voltage of a first voltage on the basis of the signal indicating the high temperature state, and operating a low VT part including a second transistor with a threshold voltage of a second voltage lower than the first voltage on the basis of the signal indicating the low temperature state.

4. The method of operating a semiconductor device according to claim 3, wherein the step of operating the high VT part and the low VT part includes the steps of:

outputting a first signal on the basis of the signal indicating the high temperature state; and

supplying power to the high VT logic circuit including the first transistor, on the basis of the first signal.

5. The method of operating a semiconductor device according to claim 3, wherein the step of operating the high VT part and the low VT part includes the steps of:

outputting a second signal on the basis of the signal indicating the low temperature state; and

supplying power to the low VT logic circuit including the second transistor, on the basis of the second signal.

6. The method of operating a semiconductor device according to claim 4, wherein the step of operating the high VT part and the low VT part includes the steps of:

outputting a second signal on the basis of the signal indicating the low temperature state; and

supplying power to the low VT logic circuit including the second transistor, on the basis of the second signal.