US4740742A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voltage regulator start-up circuit
Assignee: Cherry Semiconductor Corp
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Filing: 1987-04-02
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Granted: 1988-04-26
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Expires: 2007-04-02
Abstract
Abstract A start-up circuit for a voltage regulator having a first current mirror for providing start-up current and a second current mirror responsive to voltage output from said regulator for turning off said first current mirror when said regulator is close to regulation. The circuitry providing start-up current and the circuitry turning off the start-up current having substantially the same temperature coefficients.
Inventors
- 👤 Walter S. Gontowski, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:03
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/26; G05F3/265; Y; Y10; Y10S; Y10S323/00; Y10S323/901; Y10S323/907
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
111 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; start-up means responsive to said input current for providing start-up current to said regulator, said start-up means having a temperature coefficient; means for receiving a regulated voltage from said regulator; shutoff circuit means responsive to said regulated voltage for shutting off said start-up circuit means, said shutoff circuit means having a temperature coefficient which is substantially the same as the temperature coefficient of said start-up means; and means, connected to said shutoff circuit means, for providing a signal when said start-up means is shut off so as to indicate when said voltage regulator is close to regulation.
Claim 2
Dependent Claim
111 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; start-up means responsive to said input current for providing start-up current to said regulator, said start-up means having a temperature coefficient; means for receiving a regulated voltage from said regulator; shutoff circuit means responsive to said regulated voltage for shutting off said start-up circuit means, said shutoff circuit means having a temperature coefficient which is substantially the same as the temperature coefficient of said start-up means; and means, connected to said shutoff circuit means, for providing a signal when said start-up means is shut off so as to indicate when said voltage regulator is close to regulation.
Claim 3
Dependent Claim
35 words
The startup circuit of claim 1 wherein said start-up means comprises a first current mirror having an input branch for receiving said input current and an output branch for providing start-up current to said regulator.
Claim 4
Dependent Claim
21 words
The start-up circuit of claim 1 wherein said means for providing an input current comprises a voltage source and a resistor.
Claim 5
Dependent Claim
51 words
The start-up circuit of claim 1 wherein said shutoff circuit means comprises a resistor for generating a shutoff current in response to said regulated voltage and a current mirror having an input branch for receiving said shutoff current and an output branch for diverting said input current from said start-up means.
Claim 6
Dependent Claim
36 words
The start-up circuit of claim 4 further comprising means, connected to said resistor, for providing a signal when said start-up means is shut off so as to indicate when said voltage regulator is close to regulation.
Claim 7
Dependent Claim
73 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; a first current mirror having an input branch for receiving said input current and an output branch for providing start-up current to said regulator; means for receiving a voltage output from said regulator; means for generating a shutoff current in response to said regulated voltage; and means responsive to said shutoff current for shutting off said first current mirror.
Claim 8
Dependent Claim
73 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; a first current mirror having an input branch for receiving said input current and an output branch for providing start-up current to said regulator; means for receiving a voltage output from said regulator; means for generating a shutoff current in response to said regulated voltage; and means responsive to said shutoff current for shutting off said first current mirror.
Claim 9
Dependent Claim
21 words
The start-up circuit of claim 6 wherein said means for providing an input current comprises a voltage source and a resistor.
Claim 10
Dependent Claim
17 words
The start-up circuit of claim 6 wherein said means for generating a shutoff current comprises a resistor.
Claim 11
Dependent Claim
44 words
The start-up circuit of claim 6 wherein said means for shutting off said first current mirror comprises a second current mirror having an input branch for receiving said shutoff current and an output branch for diverting said input current from said first current mirror.
Claim 12
Dependent Claim
25 words
The start-up circuit of claim 6 further comprising means connected to said first current mirror for indicating when said voltage regulator is close to regulation.
Claim 13
Dependent Claim
104 words
A start-up circuit for a voltage regulator comprising: means for providing an input voltage; an input resistor for receiving said input voltage and providing an input current; a first current mirror having a diode for receiving said input current and a transistor for providing start-up current to said regulator; means for receiving a regulated voltage output from said regulator; a resistor connected to said regulated voltage receiving means for providing a shutoff current; and a second current mirror having a diode for receiving said shutoff current and a transistor for diverting said input current from said first current mirror to turnoff said start-up current.
Claim 14
Dependent Claim
104 words
A start-up circuit for a voltage regulator comprising: means for providing an input voltage; an input resistor for receiving said input voltage and providing an input current; a first current mirror having a diode for receiving said input current and a transistor for providing start-up current to said regulator; means for receiving a regulated voltage output from said regulator; a resistor connected to said regulated voltage receiving means for providing a shutoff current; and a second current mirror having a diode for receiving said shutoff current and a transistor for diverting said input current from said first current mirror to turnoff said start-up current.
Claim 15
Dependent Claim
42 words
The start-up circuit of claim 11 further comprising means connected between said input resistor and said first current mirror for providing a signal when said first current mirror is shut off so as to indicate when said regulator is close to regulation.
Claim 16
Dependent Claim
90 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; a current mirror having an input branch for receiving said input current and an output branch for providing a start-up current to said regulator, said current mirror having a temperature coefficient; means for receiving a regulated voltage from said regulator; and shut-off circuit means responsive to said regulated voltage for shutting off said current mirror, said shut-off circuit means having a temperature coefficient which is substantially the same as the temperature coefficient of said current mirror.
Claim 17
Dependent Claim
90 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; a current mirror having an input branch for receiving said input current and an output branch for providing a start-up current to said regulator, said current mirror having a temperature coefficient; means for receiving a regulated voltage from said regulator; and shut-off circuit means responsive to said regulated voltage for shutting off said current mirror, said shut-off circuit means having a temperature coefficient which is substantially the same as the temperature coefficient of said current mirror.
Claim 18
Dependent Claim
109 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; start-up means responsive to said input current for providing start-up current to said regulator, said start-up means having a temperature coefficient; means for receiving a regulated voltage from said regulator; a resistor for generating a shut-off current in response to said regulated voltage; and a current mirror having an input branch for receiving said shut-off current and an output branch for diverting said input current from said start-up means to shut off said start-up means, said current mirror having a temperature coefficient which is substantially the same as the temperature coefficient of said start-up means.
Claim 19
Dependent Claim
109 words
A start-up circuit for a voltage regulator comprising: means for providing an input current; start-up means responsive to said input current for providing start-up current to said regulator, said start-up means having a temperature coefficient; means for receiving a regulated voltage from said regulator; a resistor for generating a shut-off current in response to said regulated voltage; and a current mirror having an input branch for receiving said shut-off current and an output branch for diverting said input current from said start-up means to shut off said start-up means, said current mirror having a temperature coefficient which is substantially the same as the temperature coefficient of said start-up means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-26 | 1991-10-26 | 1992-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-26 | 1995-10-26 | 1996-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-26 | 1999-10-26 | 2000-04-26 | $7700.00 | Window Closed / Lapsed |