US3852679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current mirror amplifiers
Assignee: RCA Corp
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Filing: 1972-12-26
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Granted: 1974-12-03
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Expires: 1992-12-26
Abstract
Abstract A current mirror amplifier for combining the output currents of an MOS source-coupled differential amplifier comprises first and second bipolar transistors having parallelled base-emitter circuits including emitter degenerative resistors. A similar resistor judicially placed in the collector circuit of one of these bipolar transistors ensures that the differential amplifier will not exhibit an offset potential between its input terminals caused by its component devices being subjected to different conditions of quiescent drain biasing when the differential amplifier supplies its combined output currents by direct coupling to a subsequent grounded-emitter amplifier stage.
Inventors
- 👤 O Schade
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 09:24
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45076; H03F3/4508; G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/26; G05F3/267; H03F3/34; H03F3/343; H03F3/347; H03F3/45179; H03F3/45183; H03F3/45479; H03F3/45632; H03F3/45744; H03F3/45766; H03F2203/00; H03F2203/45; H03F2203/45594; H03F2203/45674; H03F2203/45676; H03F2203/45686; H03F2203/45688; H03F2203/45696
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
360 words
A differential amplifier comprising: first and second input terminals for application of first and second input currents, respectively, with quiescent components being proportionally related in a ratio of m to l, m being a positive number; a common terminal; an output terminal; first and second and third transistors of the same conductivity type, having respective base and emitter and collector electrodes, the transconductance versus base-emitter potential characteristics of said first and said second transistors being proportionally related in a ratio of m to l; first and second and third direct coupling means having substantially identical potential translation characteristics, said first direct coupling means being the sole means for direct coupling said first input terminal to said first transistor base electrode, said second direct coupling means being the sole means for direct coupling said first input terminal to said second transistor base electrode; means direct current conductively coupling said first transistor collector electrode to said first input terminal; first and second and third resistive elements having respective resistances proportionally related to each other in a ratio of l to m to m, said fiRst resistive element connecting said first transistor emitter electrode to said common terminal for conducting the entire emitter current of said first transistor, said second resistive element connecting said second transistor emitter electrode to said common terminal for conducting the entire emitter current of said second transistor, said third resistive element being connected at a first of its ends to said second input terminal and being connected at a second of its ends to said second transistor collector electrode such that the entire collector current of said second transistor flows through said third resistive element; and means for connecting said third transistor as a common-emitter amplifier including a direct connection of its emitter electrode to said common terminal, a connection of its collector electrode to said output terminal and direct coupling of the second end of said third resistive element to said third transistor base electrode by said third direct coupling means, said differential amplifier being operative under the aforeclaimed input current conditions to maintain substantially equal quiescent potentials at its said first and said second input terminals.
Claim 2
Dependent Claim
314 words
A differential amplifier comprising: a common terminal; first and second input terminals arranged for application of first and second input currents, respectively; an output terminal; first and second and third transistors each having a base and an emitter electrode with a semiconductor junction therebetween and each having a collector electrode, said third transistor emitter electrode being directly connected to said common terminal; first, second and third resistive elements, each having first and second ends, said second and said third resistive elements having substantially equal resistances, said first and said second resistive elements having their respective first ends directly connected respectively to said first transistor emitter electrode and to said second transistor emitter electrode and having their second ends directly connected to said common terminal; means for direct current conductively coupling said first transistor collector electrode to said first input terminal; means for direct current conductively coupling said second transistor collector electrode to said second input terminal via a path passing through said third resistor included therewithin, the first end of said third resistor being connected to said second input terminal; first direct coupling means connecting said first input terminal to said first transistor base electrode thereby to regulate the potential between said first input terminal and said first transistor emitter electrode to be substantially equal to an integral multiple of offset potential developed across said first transistor semiconductor junction in response to said first input current as applied to said first input terminal; means to provide the same potential to said second transistor base electrode as to said first transistor base electrode; second direct coupling means, being of like type to said first direct coupling means and connecting the second end of said third resistor to said third transistor base electrode; and further means for connecting said third transistor in common-emitter amplifier configuration including a connection of said output terminal to its collector electrode.
Claim 3
Dependent Claim
314 words
A differential amplifier comprising: a common terminal; first and second input terminals arranged for application of first and second input currents, respectively; an output terminal; first and second and third transistors each having a base and an emitter electrode with a semiconductor junction therebetween and each having a collector electrode, said third transistor emitter electrode being directly connected to said common terminal; first, second and third resistive elements, each having first and second ends, said second and said third resistive elements having substantially equal resistances, said first and said second resistive elements having their respective first ends directly connected respectively to said first transistor emitter electrode and to said second transistor emitter electrode and having their second ends directly connected to said common terminal; means for direct current conductively coupling said first transistor collector electrode to said first input terminal; means for direct current conductively coupling said second transistor collector electrode to said second input terminal via a path passing through said third resistor included therewithin, the first end of said third resistor being connected to said second input terminal; first direct coupling means connecting said first input terminal to said first transistor base electrode thereby to regulate the potential between said first input terminal and said first transistor emitter electrode to be substantially equal to an integral multiple of offset potential developed across said first transistor semiconductor junction in response to said first input current as applied to said first input terminal; means to provide the same potential to said second transistor base electrode as to said first transistor base electrode; second direct coupling means, being of like type to said first direct coupling means and connecting the second end of said third resistor to said third transistor base electrode; and further means for connecting said third transistor in common-emitter amplifier configuration including a connection of said output terminal to its collector electrode.
Claim 4
Dependent Claim
154 words
A differential amplifier as claimed in claim 2 wherein said first and second resistive elements are of substantially equal resistance, having in combination therewith: first and second semiconductor amplifier devices of a complementary conductivity type to said first and said second transistors, each of which said amplifier devices has an input electrode, said first and said second amplifier devices having output electrodes respectively connected to said first and said second input terminals; means for providing operating currents to the common electrodes of said first and said second semicoNductor amplifier devices; and means for providing similar quiescent bias conditions to each of said input electrodes of said first and said second semiconductor amplifier devices as referred to said common terminal, thereby conditioning said first and said second semiconductor amplifier devices to provide said first input current and said second input current respectively from their respective output electrodes which receive substantially equal quiescent potentials in return.
Claim 5
Dependent Claim
266 words
In a differential amplifier comprising first and second transistors, each having a base and an emitter and a collector electrode, a first and a second input terminal, means for direct current conductively coupling said first input terminal to said first transistor collector electrode, means for direct current conductively coupling said second input terminal to said second transistor collector electrode, a common terminal, first and second emitter resistances of substantially equal resistance value R respectively connecting separate ones of said emitter electrodes of said first and said second transistors each to said common terminal, substantially identical means for direct coupling each of said base electrodes of said first and said second transistors to said first input terminal, said means for direct coupling said first transistor base electrode to said first terminal in combination with said first transistor and with said means for direct current conductively coupling said first terminal to said first transistor collector electrode forming a negative feedback loop for regulating the potential between said input terminal and said first transistor emitter electrode to a first value, and output load means having an input port connected between said second transistor collector electrode and said common terminal and exhibiting regulatory action to maintain the potential across its input port at a second value substantially equal to but somewhat smaller than said first value, the improvement comprising: a first collector resistance of said resistance value R, included in said means for direct current conductively coupling said second input terminal to said second transistor collector electrode and connected between said second input terminal and said second transistor collector electrode.
Claim 6
Dependent Claim
266 words
In a differential amplifier comprising first and second transistors, each having a base and an emitter and a collector electrode, a first and a second input terminal, means for direct current conductively coupling said first input terminal to said first transistor collector electrode, means for direct current conductively coupling said second input terminal to said second transistor collector electrode, a common terminal, first and second emitter resistances of substantially equal resistance value R respectively connecting separate ones of said emitter electrodes of said first and said second transistors each to said common terminal, substantially identical means for direct coupling each of said base electrodes of said first and said second transistors to said first input terminal, said means for direct coupling said first transistor base electrode to said first terminal in combination with said first transistor and with said means for direct current conductively coupling said first terminal to said first transistor collector electrode forming a negative feedback loop for regulating the potential between said input terminal and said first transistor emitter electrode to a first value, and output load means having an input port connected between said second transistor collector electrode and said common terminal and exhibiting regulatory action to maintain the potential across its input port at a second value substantially equal to but somewhat smaller than said first value, the improvement comprising: a first collector resistance of said resistance value R, included in said means for direct current conductively coupling said second input terminal to said second transistor collector electrode and connected between said second input terminal and said second transistor collector electrode.
Claim 7
Dependent Claim
54 words
In an improved differential amplifier as claimed in claim 4, the refinement comprising: a second collector resistance of said resistance value R included in said means for direct current conductively coupling said first transistor collector electrode to said first input terminal and connected between said first input terminal and said first transistor collector electrode.
Claim 8
Dependent Claim
151 words
An amplifier including the improved differential amplifier claimed in claim 4, having: third and fourth transistors, each having an input electrode and an output electrode and a common electrode, and means for connecting said third and said fourth transistors in a further differential amplifier configuration with their common electrodes coupled to each other and to said common terminal, their input electrodes adapted to receive input signals and their output electrodes respectively connected to said first and said second input terminals; and having included within said output load means: a fifth transistor, which is of the same conductivity type as said first and said second transistors and has a base and an emitter and a collector electrode and means connecting said fifth transistor in a common-emitter amplifier configuration including the direct coupling of its base electrode to said output terminal and the direct connection of its emitter electrode to said common terminal.
Claim 9
Dependent Claim
254 words
In a differential amplifier comprising first and second and a third and a fourth and fifth transistors each having a base and an emitter and a collector electrode, a first input terminal direct coupled to said third transistor base electrode, means for direct current conductively coupling said first traNsistor collector electrode to said first input terminal, a second input terminal direct current conductively coupled to said third transistor collector electrode, a common terminal, an output terminal directly connected to said fifth transistor collector electrode, said second transistor collector electrode being direct current conductively coupled to said third transistor emitter electrode, first and second emitter resistances of substantially equal resistance value R respectively connecting separate ones of said emitter electrodes of said first and said second transistors each to said common terminal, substantially identical means direct coupling each of the base electrodes of said first and said second transistors to said third transistor emitter electrode, and means for connecting the fourth and fifth transistors as a direct coupled amplifier cascade configuration with said fourth transistor base electrode connected to said third transistor collector electrode and with said fifth transistor base electrode connected to said fourth transistor emitter electrode and with said fifth transistor emitter electrode directly connected to said common terminal, the improvement comprising: a first collector resistance of said resistance value R included in said means for direct current conductively coupling said second input terminal and said third transistor collector electrode and connected between said second input terminal and said fourth transistor base electrode.
Claim 10
Dependent Claim
254 words
In a differential amplifier comprising first and second and a third and a fourth and fifth transistors each having a base and an emitter and a collector electrode, a first input terminal direct coupled to said third transistor base electrode, means for direct current conductively coupling said first traNsistor collector electrode to said first input terminal, a second input terminal direct current conductively coupled to said third transistor collector electrode, a common terminal, an output terminal directly connected to said fifth transistor collector electrode, said second transistor collector electrode being direct current conductively coupled to said third transistor emitter electrode, first and second emitter resistances of substantially equal resistance value R respectively connecting separate ones of said emitter electrodes of said first and said second transistors each to said common terminal, substantially identical means direct coupling each of the base electrodes of said first and said second transistors to said third transistor emitter electrode, and means for connecting the fourth and fifth transistors as a direct coupled amplifier cascade configuration with said fourth transistor base electrode connected to said third transistor collector electrode and with said fifth transistor base electrode connected to said fourth transistor emitter electrode and with said fifth transistor emitter electrode directly connected to said common terminal, the improvement comprising: a first collector resistance of said resistance value R included in said means for direct current conductively coupling said second input terminal and said third transistor collector electrode and connected between said second input terminal and said fourth transistor base electrode.
Claim 11
Dependent Claim
35 words
In an improved differential amplifier as claimed in claim 7, the refinement comprising: a semiconductor diode included within said means for direct current conductively coupling said first transistor collector electrode to said first input terminal.
Claim 12
Dependent Claim
102 words
An amplifier including the improved differential amplifier claimed in claim 8 and having: sixth and seventh transistors, each having an input electrode and an output electrode and a common electrode, and means for connecting said sixth and said seventh transistors in a further differential amplifier configuration with their common electrodes coupled to each other and to said common terminal, their input electrodes adapted to receive input signals and their output electrodes respectively connected to said first and said second input terminals to provide respectively first and second currents responsive to said input signals and to receive substantially equal quiescent potentials in return.
Claim 13
Dependent Claim
291 words
In a differential amplifier comprising first and second and third transistors each having a base and an emitter and a collector electrode, a first input terminal direct coupled to said third transistor base electrode, means for direct current conductively coupling said first transistor collector electrode to said first input terminal, means direct current conductively coupling said second transistor collector electrode to said third transistor emitter electrode, a second input terminal, means direct current conductively coupling said third transistor collector electrode to said second input terminal, a common terminal, first and second emitter resistances of substantially equal resistance value R respectively connecting separate ones of said emitter electrodes of said first and said second transistors each to said common terminal, substantially identical means direct coupling each of said base electrodes of said first and said second transistors to said first input terminal, said means for direct current conductively coupling said first transistor collector electrode to said first input terminal in combination with said first transistor and with said means direct coupling said first transistor base electrode to said first input terminal forming a negative feedback loop for regulating the potential between said input terminal and said first transistor emitter electrode to a first value, output load means having an input port connected between said third transistor collector electrode and said common terminal and exhibiting regulatory actiOn to maintain the potential across its input port at a second value substantially equal to but somewhat smaller than said first value, the improvement comprising: a first collector resistance of said resistance value R included in said means for direct current conductively coupling said third transstor collector electrode to said second input terminal and connected between said second input terminal and said third transistor collector electrode.
Claim 14
Dependent Claim
291 words
In a differential amplifier comprising first and second and third transistors each having a base and an emitter and a collector electrode, a first input terminal direct coupled to said third transistor base electrode, means for direct current conductively coupling said first transistor collector electrode to said first input terminal, means direct current conductively coupling said second transistor collector electrode to said third transistor emitter electrode, a second input terminal, means direct current conductively coupling said third transistor collector electrode to said second input terminal, a common terminal, first and second emitter resistances of substantially equal resistance value R respectively connecting separate ones of said emitter electrodes of said first and said second transistors each to said common terminal, substantially identical means direct coupling each of said base electrodes of said first and said second transistors to said first input terminal, said means for direct current conductively coupling said first transistor collector electrode to said first input terminal in combination with said first transistor and with said means direct coupling said first transistor base electrode to said first input terminal forming a negative feedback loop for regulating the potential between said input terminal and said first transistor emitter electrode to a first value, output load means having an input port connected between said third transistor collector electrode and said common terminal and exhibiting regulatory actiOn to maintain the potential across its input port at a second value substantially equal to but somewhat smaller than said first value, the improvement comprising: a first collector resistance of said resistance value R included in said means for direct current conductively coupling said third transstor collector electrode to said second input terminal and connected between said second input terminal and said third transistor collector electrode.
Claim 15
Dependent Claim
84 words
An amplifier, including the improved differential amplifier claimed in claim 10 and having: fourth and fifth transistors, each having an input electrode and an output electrode and a common electrode, and means for connecting said fourth and said fifth transistors in a further differential amplifier configuration with their common electrodes coupled to each other and to said common terminal, their input electrodes adapted to receive input signals and their output electrodes respectively connected to separate ones of said first and said second input terminals.
Claim 16
Dependent Claim
143 words
A current mirror amplifier comprising: an input, a common and an output terminals; a first, a second and a third transistors each having a base electrode, an emitter electrode and a collector electrode; means for similarly direct current conductively coupling said first and said second transistor emitter electrodes to said common terminal; means for similarly direct coupling said third transistor emitter electrode to said base electrodes of said first and said second transistors; means for direct current conductively coupling said second transistor collector electrode to said third transistor emitter electrode; means for maintaining said third transistor base electrode at substantially the same potential as appears at said input terminal; means for direct current conductively coupling said third transistor collector electrode to said output terminal and a semiconductor diode providing direct current conductive connection of said input terminal and said first transistor collector electrode.
Claim 17
Dependent Claim
143 words
A current mirror amplifier comprising: an input, a common and an output terminals; a first, a second and a third transistors each having a base electrode, an emitter electrode and a collector electrode; means for similarly direct current conductively coupling said first and said second transistor emitter electrodes to said common terminal; means for similarly direct coupling said third transistor emitter electrode to said base electrodes of said first and said second transistors; means for direct current conductively coupling said second transistor collector electrode to said third transistor emitter electrode; means for maintaining said third transistor base electrode at substantially the same potential as appears at said input terminal; means for direct current conductively coupling said third transistor collector electrode to said output terminal and a semiconductor diode providing direct current conductive connection of said input terminal and said first transistor collector electrode.
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 |