US4616189A
Expired / Lapsed
US
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Gallium arsenide differential amplifier with closed loop bias stabilization
Assignee: Qorvo US Inc
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Filing: 1985-04-26
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Granted: 1986-10-07
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Expires: 2005-04-26
Abstract
Abstract A gallium arsenide differential amplifier is compensated against temperature and process induced variations so as to provide phase and amplitude matched differential output signals centered about an internal GaAs reference voltage. Compensation of the amplifier is effected by one or more current sources which are adjustably responsive to the dynamic common mode level of the output signals. The resultant amplifier provides a high common mode rejection ratio and facilitates implementation of otherwise impracticable differential GaAs circuit topologies.
Inventors
- 👤 M. Louis Pengue, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:55
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45076; H03F3/45376; H03F3/45381; H03F3/45479; H03F3/45632; H03F3/45636; H03F3/45641; H03F3/45645; H03F3/4565; H03F3/45659; H03K; H03K19/00; H03K19/003; H03K19/00369; H03K19/00384; H03K19/02; H03K19/08; H03K19/094; H03K19/09432; H03K19/09436; H03F2200/00; H03F2200/291; H03F2200/78; H03F2203/00; H03F2203/45; H03F2203/45008; H03F2203/45072; H03F2203/45081; H03F2203/45186; H03F2203/45418; H03F2203/45462; H03F2203/45476; H03F2203/45612; H03F2203/45658
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
207 words
A gallium arsenide (GaAs) differential voltage amplifier, compensated for temperature and process variations, comprising: signal input means for inputting an input logic signal; signal output means for outputting an output logic signal; a common source gallium arsenide field effect transistor (GaAsFET) differential amplifier comprising a pair of common source connected GaAsFETS, each having a drain coupled to a voltage input through a voltage dropping means, each GaAsFET having a gate input and a drain output, said gate inputs being coupled to the signal input means and the drain outputs providing output differential logic signals; the GaAsFET differential amplifier further including a current source means connected to the common source of the GaAsFETs for producing current flow through the GaAsFETs and the voltage dropping means, the current source means being adjustably responsive to a signal applied to a control signal input of the current source means to vary said current flow; first coupling means for coupling the differential logic signals from the GaAsFET drains to the signal output means; sampling means coupled to the GaAsFET drains for generating a true common mode signal from the differential logic signal; and second coupling means for coupling the true common mode signal to the control signal input of the current source.
Claim 2
Dependent Claim
207 words
A gallium arsenide (GaAs) differential voltage amplifier, compensated for temperature and process variations, comprising: signal input means for inputting an input logic signal; signal output means for outputting an output logic signal; a common source gallium arsenide field effect transistor (GaAsFET) differential amplifier comprising a pair of common source connected GaAsFETS, each having a drain coupled to a voltage input through a voltage dropping means, each GaAsFET having a gate input and a drain output, said gate inputs being coupled to the signal input means and the drain outputs providing output differential logic signals; the GaAsFET differential amplifier further including a current source means connected to the common source of the GaAsFETs for producing current flow through the GaAsFETs and the voltage dropping means, the current source means being adjustably responsive to a signal applied to a control signal input of the current source means to vary said current flow; first coupling means for coupling the differential logic signals from the GaAsFET drains to the signal output means; sampling means coupled to the GaAsFET drains for generating a true common mode signal from the differential logic signal; and second coupling means for coupling the true common mode signal to the control signal input of the current source.
Claim 3
Dependent Claim
49 words
An amplifier according to claim 1 in which the current source is connected in series with a voltage source and the second coupling means includes a voltage shifting means for shifting the voltage of the true common mode signal, whereby the dynamic range of the current source is enhanced.
Claim 4
Dependent Claim
43 words
An amplifier according to claim 1 in which the second coupling means includes an active means, for coupling a steady state component of the true common mode signal, shunted by a passive means, for coupling a transient component of the common mode signal.
Claim 5
Dependent Claim
28 words
An amplifier according to claim 1 in which the sampling means includes two active components symmetrically connected together and providing the common mode signal at a common junction.
Claim 6
Dependent Claim
19 words
An amplifier according to claim 1 in which a voltage source is connected in series with the current source.
Claim 7
Dependent Claim
27 words
An amplifier according to claim 1 in which the second coupling means includes a voltage shifting means for shifting the voltage of the true common mode signal.
Claim 8
Dependent Claim
27 words
An amplifier according to claim 1 in which the sampling means includes two passive components symmetrically connected together and providing the common mode signal at their junction.
Claim 9
Dependent Claim
64 words
A gallium arsenide (GaAs) translator circuit according to claim 1 for translating an input logic signal, input from a first circuit at a first set of logic levels, for output of a second set of logic levels, in which the first coupling means couples the differential logic signals from the GaAsFET drains to the signal ouptut means at the second set of logic levels.
Claim 10
Dependent Claim
27 words
A translator according to claim 8 in which the sampling means includes two passive components symmetrically connected together and providing the common mode signal at their junction.
Claim 11
Dependent Claim
28 words
A translator according to claim 8 in which the sampling means includes two active components symmetrically connected together and providing the common mode signal at a common junction.
Claim 12
Dependent Claim
19 words
A translator according to claim 8 in which a voltage source is connected in series with the current source.
Claim 13
Dependent Claim
19 words
A translator according to claim 8 in which the first coupling means includes a second GaAsFET differential voltage amplifier.
Claim 14
Dependent Claim
31 words
A translator according to claim 8 in which the first coupling means includes a first voltage shifting means for shifting the voltage of the differential logic signals from the GaAsFET drains.
Claim 15
Dependent Claim
28 words
A translator according to claim 13 in which the first voltage shifting means includes a current source having an output current responsive to the true common mode signal.
Claim 16
Dependent Claim
28 words
A translator according to claim 8 in which the second coupling means includes a second voltage shifting means for shifting the voltage of the true common mode signal.
Claim 17
Dependent Claim
44 words
A translator according to claim 8 in which the second coupling means includes an active means, for coupling a steady state component of the true common mode signal, shunted by a passive means, for coupling a transient component of the true common mode signal.
Claim 18
Independent Claim
164 words
A method for compensating a gallium arsenide differential amplifier comprising: providing a differential common source amplifier including a pair of common source connected gallium arsenide FETs (GaAsFETs), each having a drain coupled to an input voltage source through a means for dropping voltage, and also having a gate input, the amplifier further including a variable current source connected to said common source of said GaAsFETs and having adjustment means for varying output current through the current source, the GaASFETs and the voltage dropping means; applying a logic signal to the GaAsFET gates; extracting a pair of differential output signals from the GaAsFET drains; deriving a true common mode signal from the differential output signals; coupling the true common mode signal back to the adjustment means of the differential amplifier current source; and varying the output of the current source to minimize variations of the true common mode signal and to maintain phase and amplitude matched differential output signals relative to their common mode level.
Claim 19
Independent Claim
164 words
A method for compensating a gallium arsenide differential amplifier comprising: providing a differential common source amplifier including a pair of common source connected gallium arsenide FETs (GaAsFETs), each having a drain coupled to an input voltage source through a means for dropping voltage, and also having a gate input, the amplifier further including a variable current source connected to said common source of said GaAsFETs and having adjustment means for varying output current through the current source, the GaASFETs and the voltage dropping means; applying a logic signal to the GaAsFET gates; extracting a pair of differential output signals from the GaAsFET drains; deriving a true common mode signal from the differential output signals; coupling the true common mode signal back to the adjustment means of the differential amplifier current source; and varying the output of the current source to minimize variations of the true common mode signal and to maintain phase and amplitude matched differential output signals relative to their common mode level.
Claim 20
Dependent Claim
25 words
The method of claim 17 including clamping the voltage dropped across each voltage dropping means to prevent said voltage from increasing above a predetermined value.
Claim 21
Dependent Claim
29 words
The method of claim 17 including shifting the level of the true common mode signal while coupling it back to the adjustment means of the differential amplifier current source.
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) | 1989-10-06 | 1990-04-07 | 1990-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-10-06 | 1994-04-07 | 1994-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-10-06 | 1998-04-07 | 1998-10-07 | $7700.00 | Window Closed / Lapsed |