US4193039A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic zeroing system
Assignee: Valenite LLC
•
Filing: 1978-02-10
•
Granted: 1980-03-11
•
Expires: 1998-02-10
Abstract
Abstract An electronic apparatus for automatically zeroing or nulling an analog offset voltage by using multiple bit successive approximation to generate an analog zeroing voltage of equal magnitude and opposite polarity to that of the offset voltage, and then summing the zeroing voltage with the offset voltage.
Inventors
- 👤 Richard L. Massa
- 👤 Kenneth J. Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:08
CPC Classifications
G; G06; G06J; G06J1/00; G01; G01D; G01D3/00; G01D3/06; H; H03; H03M; H03M1/00; H03M1/12; H03M1/124; H03M1/129; H03M1/1295
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
206 words
Apparatus for automatically producing an analog zeroing voltage for nulling an offset voltage of either positive or negative polarity, said apparatus comprising: polarity sensing means for sensing the polarity of a signal associated with the offset signal; latch means coupled to the sensing means for providing a control signal whose state depends upon the polarity of the offset signal as determined by the sensing means; voltage generator means for producing an output voltage of a magnitude substantially the same as the offset voltage; inverter means for inverting the output voltage from the voltage generator; switch means having two inputs, a control input and an output, one input being coupled to the unchanged output of the voltage generator means, with the other input being coupled to the output of the inverter means, and the control input being coupled to the output of said latch means, operative to couple one of its inputs to its output depending on the state of the control signal from the latch means whereby a zeroing voltage is provided of the same magnitude yet of opposite polarity to that of the offset voltage; and summing means coupled to the output of said switch means for summing the zeroing voltage with the offset voltage.
Claim 2
Dependent Claim
206 words
Apparatus for automatically producing an analog zeroing voltage for nulling an offset voltage of either positive or negative polarity, said apparatus comprising: polarity sensing means for sensing the polarity of a signal associated with the offset signal; latch means coupled to the sensing means for providing a control signal whose state depends upon the polarity of the offset signal as determined by the sensing means; voltage generator means for producing an output voltage of a magnitude substantially the same as the offset voltage; inverter means for inverting the output voltage from the voltage generator; switch means having two inputs, a control input and an output, one input being coupled to the unchanged output of the voltage generator means, with the other input being coupled to the output of the inverter means, and the control input being coupled to the output of said latch means, operative to couple one of its inputs to its output depending on the state of the control signal from the latch means whereby a zeroing voltage is provided of the same magnitude yet of opposite polarity to that of the offset voltage; and summing means coupled to the output of said switch means for summing the zeroing voltage with the offset voltage.
Claim 3
Dependent Claim
61 words
Apparatus as defined in claim 1 wherein said voltage generator means further comprises: means for making a plurality of changes in the magnitude of the analog zeroing signal, each change being a fraction of the previous change, and each change being selected to drive the sum of the analog zeroing signal and the analog offset signal toward zero from one direction.
Claim 4
Dependent Claim
34 words
Apparatus as defined in claim 2 wherein said voltage generator means further comprises: cycle actuating means; oscillating means; and, a multiple-bit successive approximation register connected to said cycle actuating means and said oscillating means.
Claim 5
Dependent Claim
21 words
Apparatus as defined in claim 3 wherein said cycle actuating means consists of a toggle switch or a remote contact closure.
Claim 6
Dependent Claim
15 words
Apparatus as defined in claim 3 wherein said oscillating means further comprises: an electronic oscillator.
Claim 7
Dependent Claim
19 words
Apparatus as defined in claim 1 wherein said polarity sensing means comprises: a comparator connected to an exclusive OR-gate.
Claim 8
Dependent Claim
14 words
Apparatus as defined in claim 1 wherein said latch means comprises: an electronic flip-flop.
Claim 9
Dependent Claim
52 words
Apparatus as defined in claim 1 wherein said inverter means further comprises: a unity gain inverter having an input and output, with said one input of said switch means being connected to the input of said inverter and the other input of said switch means connected to the output of said inverter.
Claim 10
Dependent Claim
17 words
Apparatus as defined in claim 1 wherein said summing means further comprises: a unity gain summing amplifier.
Claim 11
Dependent Claim
30 words
Apparatus as defined in claim 9 wherein said summing amplifier further comprises: an operational amplifier; and three resistors each having one end connected to the input of said operational amplifier.
Claim 12
Dependent Claim
38 words
Apparatus as recited in claim 1 further comprising: means coupled to said summing means for preventing indecision of a display device, operative to supply a predetermined voltage level to said summing means after generation of the zeroing signal.
Claim 13
Dependent Claim
80 words
Apparatus as defined in claim 11 wherein said means for preventing indecision of a display device further comprises: a voltage source coupled to a resistive voltage dividing means; and electronic analog switch means connecting said resistive voltage dividing means with said summing means, said electronic analog switch means having a control input coupled to said voltage generator means, operative to connect the output of the resistive voltage dividing means to said summing means after the generation of said zeroing voltage.
Claim 14
Dependent Claim
21 words
Apparatus as defined in claim 3 which further comprises: means for indicating an overrange condition of said multiple-bit successive approximation register.
Claim 15
Dependent Claim
95 words
Apparatus as defined in claim 13 wherein said means for indicating an overrange condition further comprises: a first NAND-gate having its inputs connected to some of a plurality of outputs of said multiple-bit successive approximation register; a second NAND-gate having its inputs connected to the remaining outputs of said multiple-bit successive approximation register; a NOR-gate having an output and two inputs, one input connected to the output of said first NAND-gate and the other input connected to the output of said second NAND-gate; and a light emitting diode connected to the output of said NOR-gate.
Claim 16
Dependent Claim
78 words
Apparatus as defined in claim 3 which further comprises: comparison means having two inputs and an output, one input being coupled to the output of said sensing means, the other input coupled to an output of the latch means, and the output coupled to a control input of the successive approximation register, operative to control the magnitude of the zeroing voltage generated by the register as a function of the comparison of the signals at its two inputs.
Claim 17
Dependent Claim
92 words
Apparatus as defined in claim 15 wherein said register includes a plurality of output lines, with said apparatus further comprising: resistive means coupled to the output lines of the register, operative to provide sequentially decreasing output voltages depending on the state of the signals on the output lines from the register; and said comparison means controlling the ultimate states of the signals on the output lines from the register wherein selected output voltages from the resistive means are utilized to form the final zeroing signal of a magnitude approximating the offset signal.
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) | 1983-03-11 | 1983-09-10 | 1984-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-11 | 1987-09-10 | 1988-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-11 | 1991-09-10 | 1992-03-11 | $7700.00 | Window Closed / Lapsed |