US3886726A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic time keeping system
Assignee: Texas Instruments Inc
•
Filing: 1972-06-19
•
Granted: 1975-06-03
•
Expires: 1992-06-19
Abstract
Abstract An electronic timekeeping device includes bipolar integrated circuit implemented logic in combination with a liquid crystal display. The bipolar circuitry is configured to effectively implement logic functions with a supply voltage of only one volt. Drive circuitry is coupled to the liquid crystal display to effectively impress an a.c. voltage across the liquid crystal cell when display is required. The logic circuitry includes a transistor configured current source regulated to effectively maintain a current independent of source and load variations, enabling integrated circuit implementation without utilizing large value external resistors. The display circuitry includes logic for enabling display of the calendar date and time, reset capabilities independent of date increments are provided.
Inventors
- 👤 Clark R Williams
- 👤 Robert H Schnurr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:32
CPC Classifications
G; G04; G04G; G04G99/00; G04C; G04C10/00; G04C9/00; G04G17/00; G04G17/02; G04G19/00; G04G5/00; G04G5/04; G04G9/00; G04G9/0023; G04G9/0029; G04G9/0047; G04G9/08; G04G9/12; G04G9/126; H; H03; H03K; H03K3/00; H03K3/01; H03K3/012; H03K3/02; H03K3/26; H03K3/28; H03K3/281; H03K3/286; H03K3/289; H10; H10D; H10D99/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
157 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for producing constant current from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupLed to said frequency source for providing a system clock signal; d. logic means including counter means responsive to said system clock signal and operative to provide time data, said counter means being implemented by current driven bipolar integrated circuitry coupled to and driven by said current regulator means; e. display means having a plurality of display elements for respectively displaying time data, and f. voltage drive circuit means coupled to said display means and said logic means, said voltage drive circuit means being operable to impress drive voltages across said display in accordance with said time data. g. time setting means coupled to the logic means for setting the status of the respective display elements independently of the other elements.
Claim 2
Dependent Claim
157 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for producing constant current from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupLed to said frequency source for providing a system clock signal; d. logic means including counter means responsive to said system clock signal and operative to provide time data, said counter means being implemented by current driven bipolar integrated circuitry coupled to and driven by said current regulator means; e. display means having a plurality of display elements for respectively displaying time data, and f. voltage drive circuit means coupled to said display means and said logic means, said voltage drive circuit means being operable to impress drive voltages across said display in accordance with said time data. g. time setting means coupled to the logic means for setting the status of the respective display elements independently of the other elements.
Claim 3
Dependent Claim
157 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for producing constant current from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupLed to said frequency source for providing a system clock signal; d. logic means including counter means responsive to said system clock signal and operative to provide time data, said counter means being implemented by current driven bipolar integrated circuitry coupled to and driven by said current regulator means; e. display means having a plurality of display elements for respectively displaying time data, and f. voltage drive circuit means coupled to said display means and said logic means, said voltage drive circuit means being operable to impress drive voltages across said display in accordance with said time data. g. time setting means coupled to the logic means for setting the status of the respective display elements independently of the other elements.
Claim 4
Dependent Claim
157 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for producing constant current from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupLed to said frequency source for providing a system clock signal; d. logic means including counter means responsive to said system clock signal and operative to provide time data, said counter means being implemented by current driven bipolar integrated circuitry coupled to and driven by said current regulator means; e. display means having a plurality of display elements for respectively displaying time data, and f. voltage drive circuit means coupled to said display means and said logic means, said voltage drive circuit means being operable to impress drive voltages across said display in accordance with said time data. g. time setting means coupled to the logic means for setting the status of the respective display elements independently of the other elements.
Claim 5
Dependent Claim
178 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for producing constant current from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupled to said frequency source for providing a system clock signal; d. logic means including counter means responsive to said system clock signal and operative to provide time data, said counter means being implemented by current driven bipolar integrated circuitry coupled to and driven by said current regulator means; e. display means having a plurality of display elements for respectively displaying time data, and f. a dc-dc converter for producing a relatively high display drive voltage from said battery voltage and source; g. drive circuit means coupled to said display means said logic means and said dc-dc converter, said drive circuit means being operable to impress said display drive voltage across said display in accordance with said time data. h. time setting means coupled to said logic means for setting the status of the respective display elements independently of the other elements.
Claim 6
Dependent Claim
178 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for producing constant current from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupled to said frequency source for providing a system clock signal; d. logic means including counter means responsive to said system clock signal and operative to provide time data, said counter means being implemented by current driven bipolar integrated circuitry coupled to and driven by said current regulator means; e. display means having a plurality of display elements for respectively displaying time data, and f. a dc-dc converter for producing a relatively high display drive voltage from said battery voltage and source; g. drive circuit means coupled to said display means said logic means and said dc-dc converter, said drive circuit means being operable to impress said display drive voltage across said display in accordance with said time data. h. time setting means coupled to said logic means for setting the status of the respective display elements independently of the other elements.
Claim 7
Dependent Claim
164 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for providing a plurality of constant current sources from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupled to said frequency source for providing a system clock signal; d. logic means responsive to said system clock signal and operative to provide time data signals, said logic means being implemented by current driven bipolar integrated device circuitry, said logic means being coupled to and driven by said constant current sources; e. display means having a plurality of display elements for respectively displaying time data, and f. voltage drive circuit mean coupled to said display means and said logic means, said voltage drive circuit means being operable to impress drive voltages across said display in accordance with said time data. g. time setting means coupled to said logic means for setting the status of the respective display elements independently of the other elements.
Claim 8
Dependent Claim
164 words
A battery operated electronic timekeeping device comprising in combination: a. current regulator means for providing a plurality of constant current sources from a battery voltage source on the order of 1 volt; b. a frequency source; c. first circuit means coupled to said frequency source for providing a system clock signal; d. logic means responsive to said system clock signal and operative to provide time data signals, said logic means being implemented by current driven bipolar integrated device circuitry, said logic means being coupled to and driven by said constant current sources; e. display means having a plurality of display elements for respectively displaying time data, and f. voltage drive circuit mean coupled to said display means and said logic means, said voltage drive circuit means being operable to impress drive voltages across said display in accordance with said time data. g. time setting means coupled to said logic means for setting the status of the respective display elements independently of the other elements.
Claim 9
Dependent Claim
19 words
The electronic timekeeping device of claim 2, wherein said display drive voltage is on the order of 15 volts.
Claim 10
Dependent Claim
26 words
The electronic timekeeping device of claim 2, wherein said display means includes a plurality of liquid crystal display elements for respectively displaying hours, minutes and seconds.
References Cited (Backward Citations)
US3072155A
Cited
US3596462A
Cited
US3691755A
Cited
US3733810A
Cited
US3699703A
Cited
US3668860A
Cited
US3750383A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |