US3742252A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal conversion circuit
Assignee: Woodward Inc
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Filing: 1972-01-06
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Granted: 1973-06-26
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Expires: 1992-01-06
Abstract
Abstract A circuit for producing successive pulses of equal charge content in response to successive cycles of an alternating input signal. A reference circuit supplied by a DC source establishes first, second and third voltages at successively higher DC levels. A capacitor referenced to the second DC level is selectively charged to the voltage at the third DC level during a first portion of each input cycle, while a load circuit referenced to the first voltage level is selectively controlled to provide a discharge path for the capacitor during a second portion of each input cycle, the respective voltage levels for the capacitor and the load circuit being such that the same amount of charge is transferred to the load circuit from the capacitor during each input cycle. In the preferred embodiment the load is a resistor-capacitor parallel combination so that the DC voltage developed across the load is proportional to the input frequency. Alternately, the load may be purely resistive or purely capacitive, in which case other characteristics of the load voltage vary in accordance with the frequency of the input signal.
Inventors
- 👤 R Brzostek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:54
CPC Classifications
H; H03; H03K; H03K25/00; H03K9/00; H03K9/06
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
194 words
In a signal conversion circuit for receiving an input signal which alternates between first and second voltage levels, the combination comprising a source of DC voltage, a reference control circuit connected across said DC source and having first, second and third reference terminals providing successively higher and generally constant DC voltage levels, a capacitor having one end coupled to said second reference terminal, first gating means selectively coupling the other end of said capacitor to said third reference terminal, a two-terminal electrical load having one terminal thereof coupled to said first reference terminal, second gating means selectively coupling the other terminal of said load to said other end of said capacitor, control means responsive to said input signal for a. enabling and disabling said first and second gating means respectively in response to the achievement of said first voltage level by said input signal to allow said capacitor to be charged while isolated from said load and b. enabling and disabling said second and first gating means respectively in response to the achievement of said second voltage level by said input signal so as to transfer the charge from said capacitor to said load.
Claim 2
Dependent Claim
194 words
In a signal conversion circuit for receiving an input signal which alternates between first and second voltage levels, the combination comprising a source of DC voltage, a reference control circuit connected across said DC source and having first, second and third reference terminals providing successively higher and generally constant DC voltage levels, a capacitor having one end coupled to said second reference terminal, first gating means selectively coupling the other end of said capacitor to said third reference terminal, a two-terminal electrical load having one terminal thereof coupled to said first reference terminal, second gating means selectively coupling the other terminal of said load to said other end of said capacitor, control means responsive to said input signal for a. enabling and disabling said first and second gating means respectively in response to the achievement of said first voltage level by said input signal to allow said capacitor to be charged while isolated from said load and b. enabling and disabling said second and first gating means respectively in response to the achievement of said second voltage level by said input signal so as to transfer the charge from said capacitor to said load.
Claim 3
Dependent Claim
50 words
In a signal conversion circuit, the combination according to claim 1 wherein said reference control circuit includes a temperature-stable zener diode for establishing a constant DC potential between said second and third reference terminals so that said capacitor charges to the same potential during each cycle of said input signal.
Claim 4
Dependent Claim
43 words
In a signal conversion circuit, the combination according to claim 1 further including third electronic gating means coupling said load to said second electronic gating means and means responsive to the discharged condition of said capacitor for disabling said third electronic gating means.
Claim 5
Dependent Claim
55 words
In a signal conversion circuit the combination according to claim 3 wherein said means for disabling said third electronic gating means comprises an operational amplifier having a. a pair of input terminals connected in series with said capacitor and said second electronic gating means, and b. an output terminal controlling said third electronic gating means.
Claim 6
Dependent Claim
67 words
In a signal conversion circuit, the combination according to claim 1 wherein said first and second electronic gating means are complementary field effect transistors, the gate terminals of which are connected together and coupled to said control means, and wherein said control means is responsive to said input signal to provide a gating control signal which alternates between the voltages at said first and third reference terminals.
Claim 7
Dependent Claim
131 words
In a signal conversion circuit for receiving an input signal which alternates between first and second voltage levels, the combination comprising first, second and third reference terminals providing successively higher and generally constant DC voltage levels, a capacitor having one end coupled to said second reference terminal, a two-terminal electrical load having one terminal coupled to said first reference terminal, and switching means coupled to the other end of said capacitor and responsive to said input signal for alternating connection of said capacitor between said third reference terminal and the other terminal of said load in accordance with changes of said input signal between said first and second voltage levels so that during each cycle of said input signal said capacitor is alternately charged and then discharged into said electrical load.
Claim 8
Dependent Claim
131 words
In a signal conversion circuit for receiving an input signal which alternates between first and second voltage levels, the combination comprising first, second and third reference terminals providing successively higher and generally constant DC voltage levels, a capacitor having one end coupled to said second reference terminal, a two-terminal electrical load having one terminal coupled to said first reference terminal, and switching means coupled to the other end of said capacitor and responsive to said input signal for alternating connection of said capacitor between said third reference terminal and the other terminal of said load in accordance with changes of said input signal between said first and second voltage levels so that during each cycle of said input signal said capacitor is alternately charged and then discharged into said electrical load.
Claim 9
Dependent Claim
55 words
In a signal conversion circuit, the combination according to claim 6 wherein said switching means comprises unipolar transistors between said third reference terminal and said load and between said capacitor and said load so that the amount of charge delivered to said load during each cycle of said input signal is independent of temperature variations.
Claim 10
Dependent Claim
78 words
A signal conversion circuit as set forth in claim 6 further including electronic gating means interposed between said switching means and said other terminal of said load, and amplification means having input terminals interposed between said switching means and said second reference terminal, said amplification means including means for supplying an enabling signal to said gating means while said switching means is conditioned to discharge said capacitor but terminating said enabling signal when the capacitor is fully discharged.
Claim 11
Dependent Claim
190 words
In a signal conversion circuit for receiving an input signal which alternates between first and second voltage levels, the combination comprising first, second and third reference terminals providing successively higher and generally constant DC voltage levels, a two-terminal charge accumulating device having one terminal coupled to said second reference terminal, a first gating means selectively coupling the other terminal of said charge accumulating device to said third reference terminal, a two-terminal electrical load having one terminal coupled to said first reference terminal, second electronic gating means selectively coupling the other terminal of said load to said other terminal of said charge accumulating device, and control means responsive to said input signal for a. enabling and disabling said first and second gating means respectively in response to the achievement of said first voltage level by said input signal to allow said charge accumulating device to be charged while isolated from said load and b. enabling and disabling said second and first gating means respectively in response to the achievement of said second voltage level by said input signal so as to transfer the charge from said accumulating device to said load.
Claim 12
Dependent Claim
190 words
In a signal conversion circuit for receiving an input signal which alternates between first and second voltage levels, the combination comprising first, second and third reference terminals providing successively higher and generally constant DC voltage levels, a two-terminal charge accumulating device having one terminal coupled to said second reference terminal, a first gating means selectively coupling the other terminal of said charge accumulating device to said third reference terminal, a two-terminal electrical load having one terminal coupled to said first reference terminal, second electronic gating means selectively coupling the other terminal of said load to said other terminal of said charge accumulating device, and control means responsive to said input signal for a. enabling and disabling said first and second gating means respectively in response to the achievement of said first voltage level by said input signal to allow said charge accumulating device to be charged while isolated from said load and b. enabling and disabling said second and first gating means respectively in response to the achievement of said second voltage level by said input signal so as to transfer the charge from said accumulating device to said load.
Claim 13
Dependent Claim
54 words
In a signal conversion circuit, the combination according to claim 9 wherein said two-terminal electrical load is a resistance-capacitance parallel circuit having a time constant which is long with respect to the period of said input signal so that the DC voltage across said load is proportional to the frequency of said input signal.
Claim 14
Dependent Claim
48 words
In a signal conversion circuit, the combination according to claim 9 wherein said two-terminal electrical load is a purely resistive load so that the signal developed across said load in response to said alternating input signal is in the form of electrical pulses having a constant time-amplitude product.
Claim 15
Dependent Claim
47 words
In a signal conversion circuit, the combination according to claim 9 wherein said two-terminal electrical load is a purely capacitive load so that the alternating input signal produces a voltage across said capacitive load which steps to successively higher levels with each cycle of said input 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) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |