Patent US5094546A successfully refreshed from Google Patents.
US5094546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ic temperature sensor with reference voltages supplied to transistor bases
Assignee: Ricoh Co Ltd
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Filing: 1990-12-06
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Granted: 1992-03-10
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Expires: 2010-12-06
Abstract
Abstract An IC temperature sensor has a reference voltage circuit for providing a reference voltages; a voltage comparing circuit provided with first and second input transistors constructed such that a ratio of sizes of emitters of the first and second input transistors is set to a predetermined ratio; a device for inputting outputs from the reference voltage circuit to the base of the input transistors; a device for providing a predetermined potential for the other input transistor; and a device for outputting a voltage signal proportional to temperature with the difference in size between the emitters of the input transistors.
Inventors
- 👤 Takahiro Tsuji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:37
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/01
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
172 words
An IC temperature sensor comprising: a differential amplifying circuit having a first input transistor and a second input transistor, a ratio of sizes of emitters of said first input transistor and said second input transistor being set to a predetermined ratio; a reference voltage circuit for respectively supplying a first reference voltage to a base of said first input transistor and a second reference voltage to a base of said second input transistor such that electric currents flow through the emitters of said first input transistor and said second input transistor; and means for outputting a signal in accordance with a change in temperature by an output voltage generated in said differential amplifying circuit on the basis of said first reference voltage, said second reference voltage, a voltage between the base and the emitter of said first input transistor, a voltage between the base and the emitter of said second input transistor and the predetermined ratio of the sizes of the emitters of said first input transistor and said second input transistor.
Claim 2
Dependent Claim
172 words
An IC temperature sensor comprising: a differential amplifying circuit having a first input transistor and a second input transistor, a ratio of sizes of emitters of said first input transistor and said second input transistor being set to a predetermined ratio; a reference voltage circuit for respectively supplying a first reference voltage to a base of said first input transistor and a second reference voltage to a base of said second input transistor such that electric currents flow through the emitters of said first input transistor and said second input transistor; and means for outputting a signal in accordance with a change in temperature by an output voltage generated in said differential amplifying circuit on the basis of said first reference voltage, said second reference voltage, a voltage between the base and the emitter of said first input transistor, a voltage between the base and the emitter of said second input transistor and the predetermined ratio of the sizes of the emitters of said first input transistor and said second input transistor.
Claim 3
Dependent Claim
41 words
An IC temperature sensor according to claim 1, in which said reference voltage circuit has two outputs for supplying said first and second reference voltages and said first reference voltage is supplied to said first input transistor through a first resistor.
Claim 4
Dependent Claim
28 words
An IC temperature sensor according to claim 1, in which an output of said differential amplifying circuit is feedback-connected to said first input transistor through a second resistor.
Claim 5
Dependent Claim
33 words
An IC temperature sensor according to claim 1, in which said output voltage is substantially linearly related to temperature throughout a range of voltage values including the lowest potential in the sensor circuit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-03-10 | 1995-09-09 | 1996-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-10 | 1999-09-09 | 2000-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-10 | 2003-09-09 | 2004-03-10 | $7700.00 | Window Closed / Lapsed |