IP Library Granted Patent US 7,646,659
Granted Patent B2
US 7,646,659 · App. 12/350,667 · Granted Jan 12, 2010

Semiconductor device temperature sensor and semiconductor storage device

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Quick Facts
Patent No.
US 7,646,659
App. No.
12/350,667
Granted
Jan 12, 2010
Kind
B2
Abstract

A semiconductor device temperature sensor produces a reference level for temperature detection from two or more reference levels of different temperatures to detect a temperature. The temperature sensor is applied for detecting the temperature of a semiconductor storage device having a memory unit which requires a refresh action. A refresh cycle control circuit provided in the semiconductor storage device controls the cycle of the refresh action for the memory unit in response to an output of the temperature sensor.

Claims (26)

1. A semiconductor device including a temperature sensor performing temperature detection using a reference level for temperature detection,

wherein the reference level for temperature detection is produced from two adjustable reference levels composed of a low-temperature reference level and high-temperature reference level, and

wherein the reference level for temperature detection is derived from resistance division of the high-temperature reference level and the low-temperature reference level.

2. The semiconductor device as claimed in claim 1 , further comprising:

a resistance array,

wherein one end of the resistance array is supplied with the low-temperature level and the other end of the resistance array is supplied with the high-temperature level.

3. The semiconductor device as claimed in claim 1 , further comprising:

a reference level switching unit that selects one from a group of consisting of the high-temperature reference level, the low-temperature reference revel and a reference level derived from the resistance division.

4. The semiconductor device as claimed claim 1 , wherein the reference level derived from the resistance division is selected in a normal mode and one of the high-temperature reference level and the low-temperature reference level is selected in a test mode.

5. The semiconductor device as claimed in claim 1 , further comprising:

a high-temperature reference level portion that generates the high-temperature level based on a basic reference and a selection signal; and

a low-temperature reference level portion that generates the low-temperature level based on the basic reference and the selection signal.

6. The semiconductor device as claimed in claim 5 , wherein the selection signal is generated based on a fuse signal.

7. The semiconductor device as claimed in claim 6 , further comprising:

a fuse circuit that generates the fuse signal; and

a selector circuit that outputs at least one of the fuse signal and a test code based on a test mode signal.

8. The semiconductor device as claimed in claim 1 , wherein a correction is performed on the high-temperature reference level and the low-temperature reference level by a trimming based on the temperature detection.

9. A semiconductor device including a temperature sensor performing temperature detection using a reference level for temperature detection,

wherein the reference level for temperature detection is produced from two adjustable reference levels composed of a low-temperature reference level and high-temperature reference level, and

wherein the reference level for temperature detection is derived from a resistance array, one end of the resistance array is supplied with the high-temperature reference level, and the other end of the resistance array is supplies with the low-temperature reference level.

10. The semiconductor device as claimed in claim 9 , further comprising:

a reference level switching unit that selects one reference level obtained from a plurality node of the resistance array.

11. The semiconductor device as claimed in claim 10 , further comprising:

a fuse circuit that includes a fuse is cut or is not cut based on the selection of one of the high-temperature reference level and the low-temperature reference level.

12. The semiconductor device as claimed in claim 9 , wherein a first trimming on the high-temperature reference level is performed when selecting the high-temperature reference level as the reference level for temperature detection, and a second trimming on the low-temperature reference level is performed when selecting the low-reference temperature as the reference level for temperature detection.

13. The semiconductor device as claimed in claim 12 , wherein a resistance division level is derived as the reference level for temperature detection after the first trimming and the second trimming.

Assignments (4)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 27, 2015
From: FUJITSU SEMICONDUCTOR LIMITED
To: SOCIONEXT INC.
Reel/Frame 035508/0469 →
CHANGE OF NAME Recorded Jul 22, 2010
From: FUJITSU MICROELECTRONICS LIMITED
To: FUJITSU SEMICONDUCTOR LIMITED
Reel/Frame 024982/0245 →
ASSIGNMENT OF ASSIGNOR'S RIGHT, TITLE AND INTEREST Recorded Mar 5, 2010
From: FUJITSU LIMITED
To: FUJITSU MICROELECTRONICS LIMITED
Reel/Frame 024035/0224 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 22, 2009
From: SAKO, ATSUMASA
To: FUJITSU LIMITED
Reel/Frame 023261/0876 →