US4446439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency/voltage conversion circuit
Assignee: Pioneer Corp
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Filing: 1982-03-11
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Granted: 1984-05-01
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Expires: 2002-03-11
Abstract
Abstract A frequency/voltage conversion circuit is provided with a detection circuit for determining when the input frequency rises above a predetermined level which threatens to inhibit operation of flip-flop devices in the circuit. In response to the detection, a capacitor of a first charging/discharging circuit is forcibly charged to a value above a predetermined level.
Inventors
- 👤 Kastuji Mizumoto
- 👤 Katsuhiko Yaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:01
CPC Classifications
H; H03; H03K; H03K9/00; H03K9/06; G; G01; G01R; G01R23/00; G01R23/02; G01R23/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
148 words
A frequency/voltage conversion circuit, comprising; a pulse generation circuit for generating a pulse signal having a period in accordance with a frequency of a given signal; a Flip-Flop being set by said pulse signal; a first charging/discharging circuit which discharges while said Flip-Flop is set, and which charges in response to a control signal; means for providing said control signal to said first charging/discharging circuit when said Flip-Flop is reset; means for resetting said Flip-Flop; and a detecting circuit for monitoring the charge level of said first charging/discharging circuit and for outputting a detection signal when the charge level of said first charging/discharging circuit does not reach a predetermined reference level at a predetermined time in each period of said pulse signal; means for providing said control signal in response to said detection signal, whereby said first charging/discharging circuit is forcedly charged in response to said detection signal.
Claim 2
Dependent Claim
148 words
A frequency/voltage conversion circuit, comprising; a pulse generation circuit for generating a pulse signal having a period in accordance with a frequency of a given signal; a Flip-Flop being set by said pulse signal; a first charging/discharging circuit which discharges while said Flip-Flop is set, and which charges in response to a control signal; means for providing said control signal to said first charging/discharging circuit when said Flip-Flop is reset; means for resetting said Flip-Flop; and a detecting circuit for monitoring the charge level of said first charging/discharging circuit and for outputting a detection signal when the charge level of said first charging/discharging circuit does not reach a predetermined reference level at a predetermined time in each period of said pulse signal; means for providing said control signal in response to said detection signal, whereby said first charging/discharging circuit is forcedly charged in response to said detection signal.
Claim 3
Dependent Claim
39 words
A frequency/voltage conversion circuit as claimed in claim 1, said resetting means comprising a reset circuit for resetting said Flip-Flop when the output voltage of said first charging/discharging circuit reaches a second reference level lower than said predetermined level.
Claim 4
Dependent Claim
40 words
A frequency/voltage conversion circuit as claimed in claim 2, further including a signal generation circuit for generating a hold signal and a reset signal in accordance with the output voltage of said first charging/discharging circuit while said Flip-Flop is set.
Claim 5
Dependent Claim
33 words
A frequency/voltage conversion circuit as claimed in claim 3, further comprising a second charging/discharing circuit discharging in response to the output from said reset circuit, and charging in response to said reset signal.
Claim 6
Dependent Claim
41 words
A frequency/voltage conversion circuit as claimed in claim 4, further including a circuit for sample-holding an output voltage of said second charging/discharing circuit in response to said hold signal, an output voltage of said circuit being obtained as a converted voltage.
Claim 7
Dependent Claim
46 words
A frequency/voltage conversion circuit as claimed in claim 5, including comparison circuit means receiving the output voltage of said first charging/discharging circuit, said comparison circuit outputting a first signal when the output voltage is higher than a third reference level higher than said predetermined reference level.
Claim 8
Dependent Claim
33 words
A frequency/voltage conversion circuit as claimed in claim 6, including AND means receiving an output from said Flip-Flop and said output of said comparison circuit, and issuing said hold signal in response thereto.
Claim 9
Dependent Claim
66 words
A frequency/voltage conversion circuit as claimed in claim 7, including further AND means receiving a second output signal from said comparison circuit when the output voltage of said first charging/discharging circuit is lower than said second reference level, and being operable to output said reset signal in response thereto, and a charging circuit operating in response to said reset signal for charging said second charging/discharging circuit.
Claim 10
Dependent Claim
30 words
A frequency/voltage conversion circuit as claimed in claim 1, further including switching circuit means operating in response to said Flip-Flop for controlling charging and discharging of said first charging/discharging circuit.
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) | 1987-05-01 | 1987-10-31 | 1988-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-01 | 1991-10-31 | 1992-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-01 | 1995-10-31 | 1996-05-01 | $7700.00 | Window Closed / Lapsed |