US3571694A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dc voltage regulator employing an fet constant current source and current flow indicator
Assignee: Honeywell Inc
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Filing: 1968-08-08
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Granted: 1971-03-23
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Expires: 1988-08-08
Abstract
Abstract A DC voltage regulator employing a constant current source and a voltage reference source to control a variable impedance to regulate an input voltage. A low voltage sensing output is provided by using a sensing transistor as a switch and temperature compensation element. The sensing transistor functions as a voltage responsive switch to produce a signal indicative of the level of the input voltage relative to a predetermined level. The sensing transistor is normally saturated to connect the sensing output to the ground.
Inventors
- 👤 Jack W Hunger
- 👤 David D Kemp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:44
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; Y; Y10; Y10S; Y10S323/00; Y10S323/907
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
138 words
Voltage regulator apparatus comprising: input means for connecting to a source of unregulated DC voltage; reference potential means; regulated voltage output means for connection to a load; variable impedance means connected between said input means and said regulated voltage output means, said impedance means having a voltage responsive control means; constant current means connected to said input means and having an output; voltage reference means connected to said reference potential means and said output of said constant current means, for providing a reference voltage at a first terminal, said voltage reference means including a means responsive to the current therethrough for producing a voltage signal at a second terminal; means connecting said first terminal to said control means of said variable impedance means; and voltage sensing means, including a voltage responsive switching means, connected to said second terminal.
Claim 2
Dependent Claim
138 words
Voltage regulator apparatus comprising: input means for connecting to a source of unregulated DC voltage; reference potential means; regulated voltage output means for connection to a load; variable impedance means connected between said input means and said regulated voltage output means, said impedance means having a voltage responsive control means; constant current means connected to said input means and having an output; voltage reference means connected to said reference potential means and said output of said constant current means, for providing a reference voltage at a first terminal, said voltage reference means including a means responsive to the current therethrough for producing a voltage signal at a second terminal; means connecting said first terminal to said control means of said variable impedance means; and voltage sensing means, including a voltage responsive switching means, connected to said second terminal.
Claim 3
Dependent Claim
14 words
Apparatus as recited in claim 1 wherein said variable impedance means is a transistor.
Claim 4
Dependent Claim
15 words
Apparatus as recited in claim 1 wherein said voltage reference means includes temperature compensation means.
Claim 5
Dependent Claim
20 words
Apparatus as recited in claim 8 wherein said voltage reference means includes a transistor operated in reverse emitter-base breakdown region.
Claim 6
Dependent Claim
53 words
Apparatus as recited in claim 1 wherein said means for supplying a constant current comprises: a junction field effect transistor having gate, source and drain electrodes; and a resistor connected between said drain electrode and said gate electrode whereby a constant current tends to flow between said source electrode and said drain electrode.
Claim 7
Dependent Claim
17 words
Apparatus cLaimed in claim 1 wherein said voltage sensing means is a transistor operated as a switch.
Claim 8
Dependent Claim
245 words
Voltage regulator apparatus, comprising: input means for connection to a power source; reference potential means; regulated voltage output means for connection to a load; a first transistor having emitter, base and collector electrodes, said collector electrode connected to said input means, said emitter electrode connected to said regulated voltage output means; a field effect transistor, having source, drain and gate electrodes, said source electrode connected to said input means, said gate electrode connected to said base electrode of said first transistor; a first resistor connected between said drain and said gate of said field effect transistor; a second transistor, having emitter, base and collector electrodes, said base electrode connected to said collector electrode; a second resistor connected between said base electrode of said first transistor and said emitter electrode of said second transistor; a diode having an anode and a cathode, said anode connected to said base of said second transistor; a third resistor connected between said cathode of said diode and said reference potential means; a third transistor having base, emitter and collector electrodes, said base electrode connected to said cathode of said diode, said emitter electrode connected to said reference potential means; and sensing output means for indicating the presence of current flow through said diode connected to said collector electrode of said third transistor whereby the voltage at said regulated voltage output means is maintained constant with respect to said reference means and said sensing output means indicates low input voltage conditions.
Claim 9
Dependent Claim
245 words
Voltage regulator apparatus, comprising: input means for connection to a power source; reference potential means; regulated voltage output means for connection to a load; a first transistor having emitter, base and collector electrodes, said collector electrode connected to said input means, said emitter electrode connected to said regulated voltage output means; a field effect transistor, having source, drain and gate electrodes, said source electrode connected to said input means, said gate electrode connected to said base electrode of said first transistor; a first resistor connected between said drain and said gate of said field effect transistor; a second transistor, having emitter, base and collector electrodes, said base electrode connected to said collector electrode; a second resistor connected between said base electrode of said first transistor and said emitter electrode of said second transistor; a diode having an anode and a cathode, said anode connected to said base of said second transistor; a third resistor connected between said cathode of said diode and said reference potential means; a third transistor having base, emitter and collector electrodes, said base electrode connected to said cathode of said diode, said emitter electrode connected to said reference potential means; and sensing output means for indicating the presence of current flow through said diode connected to said collector electrode of said third transistor whereby the voltage at said regulated voltage output means is maintained constant with respect to said reference means and said sensing output means indicates low input voltage conditions.
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) | 1974-03-22 | 1974-09-21 | 1975-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-22 | 1978-09-21 | 1979-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-22 | 1982-09-21 | 1983-03-23 | $7700.00 | Window Closed / Lapsed |