Patent US3783400A successfully refreshed from Google Patents.
US3783400A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Differential current amplifier
Assignee: Motorola Solutions Inc
•
Filing: 1972-12-01
•
Granted: 1974-01-01
•
Expires: 1992-12-01
Abstract
Abstract A differential current amplifier suitable for realization in monolithic integrated circuit form includes a pair of input transistors supplied with differential current at the bases thereof. The emitters of the transistors are interconnected, as are the collectors, and feedback resistors are connected between the collectors and the bases of the respective transistors. A pair of output transistors have the bases coupled in common with the bases of the input transistors and the emitters connected in common with the emitters of the input transistors, so that the collectors of the output transistors then provide a differential output current in accordance with differential input current supplied to the bases of the input transistors.
Inventors
- 👤 M Gay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:38
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
290 words
A current amplifier including in combination: first and second voltage supply terminals for connection across a source of DC potential; first and second transistor means of the same conductivity type, at least said first transistor means comprising two portions and having first and second collector electrodes, at least one base electrode and at least one emitter electrode, said second transistor means having at least one collector electrode, at least one base electrode, and at least one emitter electrode, the second collector of said first transistor means and said one collector of said second transistor means being connected in common at a first junction, and the emitters of said first and second transistor means being connected with said first voltage supply terminal; first resistive impedance feedback means connected between said first junction and said one base of said first transistor means; second resistive impedance feedback means connected between said first junction and said one base of said second transistor means; third and fourth transistor means of opposite conductivity type to the conductivity type of said first and second transistor means, said third and fourth transistor means each having collector, base and emitter electrodes, the collector of said third transistor means connected with said one base of said first transistor means, the collector of said fourth transistor means connected with said one base of said second transistor means, and the emitters of said third aNd fourth transistor means connected in common at a second junction; means for supplying a differential input signal to the bases of said third and fourth transistor means; and a current source coupled between said second junction and said second voltage supply terminal, the first collector of said first transistor means providing output current from said amplifier circuit.
Claim 2
Dependent Claim
290 words
A current amplifier including in combination: first and second voltage supply terminals for connection across a source of DC potential; first and second transistor means of the same conductivity type, at least said first transistor means comprising two portions and having first and second collector electrodes, at least one base electrode and at least one emitter electrode, said second transistor means having at least one collector electrode, at least one base electrode, and at least one emitter electrode, the second collector of said first transistor means and said one collector of said second transistor means being connected in common at a first junction, and the emitters of said first and second transistor means being connected with said first voltage supply terminal; first resistive impedance feedback means connected between said first junction and said one base of said first transistor means; second resistive impedance feedback means connected between said first junction and said one base of said second transistor means; third and fourth transistor means of opposite conductivity type to the conductivity type of said first and second transistor means, said third and fourth transistor means each having collector, base and emitter electrodes, the collector of said third transistor means connected with said one base of said first transistor means, the collector of said fourth transistor means connected with said one base of said second transistor means, and the emitters of said third aNd fourth transistor means connected in common at a second junction; means for supplying a differential input signal to the bases of said third and fourth transistor means; and a current source coupled between said second junction and said second voltage supply terminal, the first collector of said first transistor means providing output current from said amplifier circuit.
Claim 3
Dependent Claim
84 words
The combination according to claim 1 wherein said current amplifier is a monolithic integrated circuit and said first and second transistor means comprise lateral PNP transistors, with said first transistor means being fabricated as a dual-collector lateral PNP transistor, the common emitter thereof comprising said one emitter of said first transistor means, the common base thereof comprising said one base of said first transistor means, and having first and second collectors corresponding to the first and second collectors, respectively, of said first transistor means.
Claim 4
Dependent Claim
23 words
The combination according to claim 2 wherein said first and second resistive feedback impedance means comprise first and second resistors of equal value.
Claim 5
Dependent Claim
16 words
The combination according to claim 3 wherein said third and fourth transistor means comprise NPN transistors.
Claim 6
Dependent Claim
50 words
The combination according to claim 1 wherein said second transistor means comprises two portions and has said one collector thereof and a second collector thereof, the first collector of said first transistor means and the second collector of said second transistor means providing differential output current from said amplifier circuit.
Claim 7
Dependent Claim
22 words
The combination according to claim 5 wherein said first and second resistive impedance means include first and second resistors of equal value.
Claim 8
Dependent Claim
65 words
The combination according to claim 5 wherein at least said first transistor means comprises a dual-collector transistor, the common emitter thereof comprising said one emitter of said first transistor means, the common base thereof comprising said one base of said first transistor means, and the first and second collector electrodes of said first transistor means comprising first and second collectors, respectively, of said dual-collector transistor.
Claim 9
Dependent Claim
26 words
The combination according to claim 7 wherein said current amplifier is fabricated as a monolithic integrated circuit and said dual-collector transistor is a lateral PNP transistor.
Claim 10
Dependent Claim
71 words
The combination according to claim 8 wherein said second transistor means comprises a second dual collector lateral PNP transistor, the common emitter thereof comprising said one emitter of said second transistor means, the common base thereof comprising said one base of said second transistor means, and said one and second collector electrodes of said second transistor means comprising first and second collectors, respectively, of said second dual collector lateral PNP transistor.
References Cited (Backward Citations)
US3536962A
Cited
US3673508A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |