US4010456A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low battery voltage indicator for a portable digital electronic instrument
Assignee: HP Inc
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Filing: 1975-03-10
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Granted: 1977-03-01
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Expires: 1995-03-10
Abstract
Abstract The output voltage of a battery in a portable digital electronic instrument is compared with an internal voltage reference. When the battery voltage falls below the reference voltage, the true decimal point of the number being displayed is not illuminated and a plurality of the adjacent decimal points are illuminated.
Inventors
- 👤 Ernst R. Erni
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:07
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/04; G06; G06F; G06F3/00; G06F3/14; G06F3/1407
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
159 words
A digital electronic instrument comprising: a battery; digital circuit means responsive to an input stimulus, said digital circuit means having a digital output; a digital display including a plurality of display modules responsive to the output of the digital circuit means, each display module having a plurality of light emitting segments for selectively displaying numerals and a decimal point, said decimal point being normally displayed in combination with a numeral on the same display module of the digital display; a reference voltage supply; and a comparator having a first input connected to the reference voltage supply, a second input connected to the battery, and an output for giving an output signal when the battery voltage is below the reference voltage, the output being connected to the digital display circuit means for causing the true decimal point to be extinguished and a plurality of the adjacent decimal points to be illuminated in response to an output signal from the comparator.
Claim 2
Dependent Claim
159 words
A digital electronic instrument comprising: a battery; digital circuit means responsive to an input stimulus, said digital circuit means having a digital output; a digital display including a plurality of display modules responsive to the output of the digital circuit means, each display module having a plurality of light emitting segments for selectively displaying numerals and a decimal point, said decimal point being normally displayed in combination with a numeral on the same display module of the digital display; a reference voltage supply; and a comparator having a first input connected to the reference voltage supply, a second input connected to the battery, and an output for giving an output signal when the battery voltage is below the reference voltage, the output being connected to the digital display circuit means for causing the true decimal point to be extinguished and a plurality of the adjacent decimal points to be illuminated in response to an output signal from the comparator.
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) | 1980-02-29 | 1980-08-30 | 1981-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-29 | 1984-08-30 | 1985-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-29 | 1988-08-30 | 1989-03-01 | $7700.00 | Window Closed / Lapsed |