US3852658A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bistable, self-compensating transducer circuit
Assignee: International Business Machines Corp
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Filing: 1973-12-26
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Granted: 1974-12-03
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Expires: 1993-12-26
Abstract
Abstract A dc coupled bistable, self-compensating transducer circuit which is capable of extracting positive or negative signals under extreme bias conditions. The circuit comprises a first differential amplifier for amplifying the input signal, a second differential amplifier connected in a compensation loop for providing negative feedback to the input signal source, and a third differential amplifier which acts as a bi-directional threshold detector with built-in trigger action and hysteresis overlap.
Inventors
- 👤 R Braun
- 👤 F Buckley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:50
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/023; H03K3/0233; H03K3/02337; G; G01; G01D; G01D3/00; G01D3/02; G01D3/021; G01R; G01R19/00; G01R19/32; H03K3/01; H03K3/013
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
152 words
A transducer circuit dc coupled to a signal source for sensing signal transitions superimposed on an undetermined or changing bias which may be larger than the signal amplitude which comprises: an input differential amplifier having its input connected directly to said signal source; a switching differential amplifier having a first input connected to the output of said input amplifier; a source of reference voltage connected to a second input of said switching amplifier; a control signal differential amplifier having a first input connected to the output of said input amplifier; means connecting a second input of said control signal amplifier to the output of said switching amplifier; means connecting said second input of the control signal amplifier to said reference voltage source; feedback connecting means from the output of said control signal amplifier to said signal source; and means associated with said control signal amplifier for filtering out high speed signal transitions.
Claim 2
Dependent Claim
152 words
A transducer circuit dc coupled to a signal source for sensing signal transitions superimposed on an undetermined or changing bias which may be larger than the signal amplitude which comprises: an input differential amplifier having its input connected directly to said signal source; a switching differential amplifier having a first input connected to the output of said input amplifier; a source of reference voltage connected to a second input of said switching amplifier; a control signal differential amplifier having a first input connected to the output of said input amplifier; means connecting a second input of said control signal amplifier to the output of said switching amplifier; means connecting said second input of the control signal amplifier to said reference voltage source; feedback connecting means from the output of said control signal amplifier to said signal source; and means associated with said control signal amplifier for filtering out high speed signal transitions.
Claim 3
Dependent Claim
189 words
A transducer circuit dc coupled to a signal source for sensing relatively fast positive or negative signal transitions superimposed on an undetermined slow changing bias larger than the signal amplitude which comprises: an input differential amplifier having its input connected directly to said signal source; a switching differential amplifier having a first input connected to the output of said input amplifier; a source of reference voltage connected to a second input of said switching amplifier; a control signal differential amplifier having a first input connected to the output of said input amplifier; means connecting a second input of said control signal amplifier to the output of said switching amplifier; means connecting said second input of the control signal amplifier to said reference voltage source; means connecting the output of said control signal amplifier to said signal source; and a damping capacitor connected to said control signal amplifier to filter out the fast signal transitions; said control signal amplifier providing negative feedback to said signal source to compensate for changing bias conditions and said switching amplifier providing output signals in response to the fast signal transitions from said signal source.
Claim 4
Dependent Claim
189 words
A transducer circuit dc coupled to a signal source for sensing relatively fast positive or negative signal transitions superimposed on an undetermined slow changing bias larger than the signal amplitude which comprises: an input differential amplifier having its input connected directly to said signal source; a switching differential amplifier having a first input connected to the output of said input amplifier; a source of reference voltage connected to a second input of said switching amplifier; a control signal differential amplifier having a first input connected to the output of said input amplifier; means connecting a second input of said control signal amplifier to the output of said switching amplifier; means connecting said second input of the control signal amplifier to said reference voltage source; means connecting the output of said control signal amplifier to said signal source; and a damping capacitor connected to said control signal amplifier to filter out the fast signal transitions; said control signal amplifier providing negative feedback to said signal source to compensate for changing bias conditions and said switching amplifier providing output signals in response to the fast signal transitions from said signal source.
Claim 5
Dependent Claim
54 words
A transducer circuit as set forth in claim 2 wherein said signal source is an optical transducer comprising: a photosensor having its output connected directly to the input of said input amplifier; and a light emitting diode signal source for said photosensor, said diode being connected to the output of said control signal amplifier.
Claim 6
Dependent Claim
52 words
A transducer circuit as set forth in claim 2 wherein said signal source is a magnetic transducer comprising: a Hall generator having its voltage electrodes connected directly to the input of said amplifier; and a control electrode on said Hall generator which is connected to the output of said control signal amplifier.
Claim 7
Dependent Claim
224 words
A bistable, self-compensating transducer circuit dc coupled to a signal source for sensing signal transitions superimposed on an undetermined or changing bias larger than the signal amplitude which comprises: an input differential amplifier having its input connected directly to said signal source; a switching differential amplifier having a first input connected to the output of said input amplifier; a source of fixed reference voltage connected to a second input of said switching amplifier for establishing a threshold whereby the output of the switching amplifier assumes either an ''''up'''' level or a ''''down'''' level dependent on the relationship between the output of the input amplifier and said fixed reference voltage; a control signal differential amplifier having a first input connected to the output of said input amplifier; means connecting a second input of said control signal amplifier to said fixed reference voltage source; means connecting said second input of the control signal amplifier to the output of said switching amplifier whereby a variable reference voltage is established at said second input which is dependent on the output of said switching amplifier; and feedback connecting means from the output of said control signal amplifier to said signal source, said control signal amplifier providing said signal source with current which varies in accordance with the relationship between the output of said amplifier and said variable reference voltage.
Claim 8
Dependent Claim
224 words
A bistable, self-compensating transducer circuit dc coupled to a signal source for sensing signal transitions superimposed on an undetermined or changing bias larger than the signal amplitude which comprises: an input differential amplifier having its input connected directly to said signal source; a switching differential amplifier having a first input connected to the output of said input amplifier; a source of fixed reference voltage connected to a second input of said switching amplifier for establishing a threshold whereby the output of the switching amplifier assumes either an ''''up'''' level or a ''''down'''' level dependent on the relationship between the output of the input amplifier and said fixed reference voltage; a control signal differential amplifier having a first input connected to the output of said input amplifier; means connecting a second input of said control signal amplifier to said fixed reference voltage source; means connecting said second input of the control signal amplifier to the output of said switching amplifier whereby a variable reference voltage is established at said second input which is dependent on the output of said switching amplifier; and feedback connecting means from the output of said control signal amplifier to said signal source, said control signal amplifier providing said signal source with current which varies in accordance with the relationship between the output of said amplifier and said variable reference voltage.
Claim 9
Dependent Claim
36 words
A bistable, self-compensating transducer circuit as set forth in claim 5 and including a damping capacitor connected to said control signal amplifier whereby only relatively slow changes in current are fed back to said signal source.
Claim 10
Dependent Claim
142 words
A bistable, self-compensating transducer circuit for sensing signal transitions superimposed on an undetermined or changing bias larger than the signal amplitude which comprises: a photosensor; a light emitting diode signal source for said photosensor; a switching differential amplifier having a first input connected to the output of said photosensor; a source of reference voltage connected to a second input of said switching amplifier; a control signal differential amplifier having a first input connected to the output of said photosensor; means connecting said reference voltage source to a second input of said control signal amplifier; means connecting the output of said switching amplifier to said second input of the control signal amplifier; feedback connecting means from the output of said control signal amplifier to said diode signal source; and means associated with said control signal amplifier for filtering out high speed signal transitions.
Claim 11
Dependent Claim
142 words
A bistable, self-compensating transducer circuit for sensing signal transitions superimposed on an undetermined or changing bias larger than the signal amplitude which comprises: a photosensor; a light emitting diode signal source for said photosensor; a switching differential amplifier having a first input connected to the output of said photosensor; a source of reference voltage connected to a second input of said switching amplifier; a control signal differential amplifier having a first input connected to the output of said photosensor; means connecting said reference voltage source to a second input of said control signal amplifier; means connecting the output of said switching amplifier to said second input of the control signal amplifier; feedback connecting means from the output of said control signal amplifier to said diode signal source; and means associated with said control signal amplifier for filtering out high speed signal transitions.
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) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |