US5391980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Second order low temperature coefficient bandgap voltage supply
Assignee: Texas Instruments Inc
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Filing: 1993-06-16
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Granted: 1995-02-21
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Expires: 2013-06-16
Abstract
Abstract A voltage reference circuit (2) is provided which includes a 2nd order curvature correction circuit (3) that eliminates undesirable 2nd order polynomial temperature dependency characteristics. A bandgap reference circuit (Q4, Q3, Q2, Q1, R2 and R1) forms a bandgap current (I X ) that is dependent upon absolute temperature. A translinear cell (Q15, Q14, Q13, Q12, Q11 and Q10) transforms this current in a squaring transformation and divides the squared current by a temperature independent current (I X ). A current mirror (Q17 and Q16) adjusts the value of the squared current so that it approximates the value of the 2nd order term of the bandgap reference circuit.
Inventors
- 👤 Frank L. Thiel
- 👤 Baoson Nguyen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:39
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/30; Y; Y10; Y10S; Y10S323/00; Y10S323/907
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
44 words
A very low temperature coefficient voltage supply, comprising: a silicon bandgap reference circuit; and a translinear squarer circuit connected to the silicon bandgap reference circuit to cancel 2nd order nonlinear temperature characteristics of the base emitter voltages of transistors of the bandgap reference circuit.
Claim 2
Dependent Claim
44 words
A very low temperature coefficient voltage supply, comprising: a silicon bandgap reference circuit; and a translinear squarer circuit connected to the silicon bandgap reference circuit to cancel 2nd order nonlinear temperature characteristics of the base emitter voltages of transistors of the bandgap reference circuit.
Claim 3
Dependent Claim
17 words
The improved bandgap reference circuit of claim 1 wherein the translinear squarer circuit is a bipolar squarer.
Claim 4
Independent Claim
90 words
A method of cancelling 2nd order temperature dependency in a bandgap reference circuit, comprising the steps of: providing a bandgap reference circuit, the bandgap reference circuit having 2nd order temperature dependence; and calculating the 2nd order temperature dependence of the bandgap reference circuit by using a translinear mathematical cell; generating a current proportional to the calculated 2nd order temperature dependence with the translinear mathematical cell; and injecting the generated proportional current into the bandgap reference cirucit, the injected current cancelling the 2nd order temperature variance of the bandgap reference circuit.
Claim 5
Independent Claim
90 words
A method of cancelling 2nd order temperature dependency in a bandgap reference circuit, comprising the steps of: providing a bandgap reference circuit, the bandgap reference circuit having 2nd order temperature dependence; and calculating the 2nd order temperature dependence of the bandgap reference circuit by using a translinear mathematical cell; generating a current proportional to the calculated 2nd order temperature dependence with the translinear mathematical cell; and injecting the generated proportional current into the bandgap reference cirucit, the injected current cancelling the 2nd order temperature variance of the bandgap reference circuit.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1998-02-20 | 1998-08-22 | 1999-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-02-20 | 2002-08-22 | 2003-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-02-20 | 2006-08-22 | 2007-02-21 | $7700.00 | Window Closed / Lapsed |