US3828345A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amplifier buffered resistance network digital to analog and analog to digital converter system
Assignee: Individual
•
Filing: 1973-01-04
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Granted: 1974-08-06
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Expires: 1993-01-04
Abstract
Abstract Voltage follower amplifiers are used between the voltage switches and the resistor network of an otherwise conventional parallel resistor network digital to analog converter. A principal advantage is that errors due to the internal resistances of the electronic voltage switches are greatly reduced.
Inventors
- 👤 T Lode
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:50
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/687; H03K17/6877; H03K17/60; H03M; H03M1/00; H03M1/66; H03M1/74
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
310 words
A digital to analog conversion system including a digital signal source providing a digital signal, an analog output terminal, a resistance network, means to connect said resistance network to said output terminal, a source of a first reference voltage, a source of a second different reference voltage, a voltage follower amplification means having an input and an output, switching means selectively connecting said first reference voltage source and said second reference voltage source to said input of said amplification means, means connecting said output of said amplification means to said resistance network, means connecting said digital signal source to said switching means such that said input of said amplification means is effectively connected to said first reference voltage source when the digital signal transmitted by said digital signal source is of a first predetermined state, and is effectively connected to said second reference voltage source when said digital signal is of a second predetermined state, said voltage follower amplification means including a voltage follower amplifier having at least one power input, and power supply means providing a plurality of power supply voltages, each referenced in a desired manner to voltage of the first and second reference voltage sources, means connecting said input of said amplification means to an input of said voltage follower amplifier, means connecting an output of said voltage follower amplifier to saId output of said amplification means, means connecting said power supply voltages to the power input of said voltage follower amplifier including means for switching the voltage on said power input in response to said digital signal such that the difference of the voltages on said input of said amplification means and on said power input remains substantially constant whether said input of said amplification means is effectively connected through said switching means to said first reference voltage source or to said second reference voltage source.
Claim 2
Dependent Claim
310 words
A digital to analog conversion system including a digital signal source providing a digital signal, an analog output terminal, a resistance network, means to connect said resistance network to said output terminal, a source of a first reference voltage, a source of a second different reference voltage, a voltage follower amplification means having an input and an output, switching means selectively connecting said first reference voltage source and said second reference voltage source to said input of said amplification means, means connecting said output of said amplification means to said resistance network, means connecting said digital signal source to said switching means such that said input of said amplification means is effectively connected to said first reference voltage source when the digital signal transmitted by said digital signal source is of a first predetermined state, and is effectively connected to said second reference voltage source when said digital signal is of a second predetermined state, said voltage follower amplification means including a voltage follower amplifier having at least one power input, and power supply means providing a plurality of power supply voltages, each referenced in a desired manner to voltage of the first and second reference voltage sources, means connecting said input of said amplification means to an input of said voltage follower amplifier, means connecting an output of said voltage follower amplifier to saId output of said amplification means, means connecting said power supply voltages to the power input of said voltage follower amplifier including means for switching the voltage on said power input in response to said digital signal such that the difference of the voltages on said input of said amplification means and on said power input remains substantially constant whether said input of said amplification means is effectively connected through said switching means to said first reference voltage source or to said second reference voltage source.
Claim 3
Dependent Claim
52 words
The combination of claim 1 further characterized by said digital signal being a digital data word coded in the form of a plurality of binary bit signals and by said first and second switching means being responsive to and controlled by the state of a predetermined one of said binary bit signals.
Claim 4
Dependent Claim
183 words
The combination of claim 2 further characterized by said voltage follower amplifier having power inputs comprising first and second power supply terminals and said power supply means providing first, second, third and fourth power supply voltages, said means for switching the voltage on said power input including first power supply connecting means connecting said first and second power supply voltages to said first power supply terminal of said voltage follower amplifier, and second power supply connecting means connecting said third and fourth power supply voltages to said second power supply terminal of said voltage follower amplifier, said first and second power supply connecting means being responsive to the state of said predetermined one of said binary bit signals such that when said binary bit signal is of a first predetermined state said power supply terminals of said voltage follower amplifier are effectively connected to said first and third power supply voltages, and when said binary bit signal is of a second predetermined state said power supply terminals of said voltage follower amplifier are effectively connected to said second and fourth power supply voltages.
Claim 5
Dependent Claim
38 words
The combination of claim 3 further characterized by the differences between said first and second reference voltages, between said first and second power supply voltages, and between said third and fourth power supply voltages respectively being substantially equal.
Claim 6
Dependent Claim
62 words
The combination of claim 3 further characterized by the values of said first, second, third, and fourth power supply voltages being such that the differences between the voltage on said input of said amplification means and the voltages on each of said power supply terminals of said voltage follower amplifier are substantially constant for the two states of said binary bit signal.
Claim 7
Dependent Claim
109 words
The combination of claim 1 further characterized by said digital to analog conversion system being incorporated in an analog to digital conversion system including an analog input signal source, means for comparing the analog signal at said analog output terminal and the analog signal from said analog input signal source, means responsive to said comparison for adjusting said digital data word transmitted by said digital data word source so as to maintain said analog signal at said analog load and said analog signal from said analog input signal source at substantial equality, digital data receiver means, and means connecting said digital signal source to said digital data receiver means.
References Cited (Backward Citations)
US2976527A
Cited
US3129420A
Cited
US3290671A
Cited
US3678504A
Cited
US3719808A
Cited
US3714599A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-05 | 1978-02-04 | 1978-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-05 | 1982-02-04 | 1982-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-05 | 1986-02-04 | 1986-08-06 | $7700.00 | Window Closed / Lapsed |