Patent US4500831A successfully refreshed from Google Patents.
US4500831A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current source
Assignee: Motorola Solutions Inc
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Filing: 1982-12-27
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Granted: 1985-02-19
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Expires: 2002-12-27
Abstract
Abstract A current source circuit is provided wherein the chip area consumption of a Miller multiplication capacitor is substantially reduced. A zero is created in addition to the pole created by the Miller multiplication capacitor. A first transistor is biased by a biasing means and has a base coupled to the emitter of a second transistor by a capacitor. The base of the second transistor is connected to the collector of the first transistor. A resistor is coupled between the emitter of the second transistor and ground.
Inventors
- 👤 M. Faheem Akram
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:45
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/22; Y; Y10; Y10S; Y10S323/00; Y10S323/907
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
246 words
A current source circuit having a first supply voltage terminal and a second supply voltage terminal, comprising: biasing means for establishing a bias voltage comprising a first transistor having a first current conducting electrode coupled to said first supply voltage terminal, a first resistor coupled to said second supply voltage terminal, and a diode coupled between said first resistor and a second current conducting electrode of said first transistor; a second transistor having a first current conducting electrode coupled to said first supply voltage terminal; a third transistor having a control electrode coupled to said second current conducting electrode of said first transistor, a first current conducting electrode coupled to a second current conducting electrode of said second transistor, and a second current conducting electrode coupled to said second supply voltage terminal; a fourth transistor having a control electrode coupled to said first current conducting electrode of said third transistor, and a first current conducting electrode coupled to said first supply voltage terminal; a capacitor coupled between said control electrode of said third transistor and a second current conducting electrode of said fourth transistor; resistive means coupled between said second current conducting electrode of said fourth transistor and said second supply voltage terminal; and a fifth transistor having a first current conducting electrode coupled to said first supply voltage terminal, a control electrode coupled to a control electrode of both said first and said second transistor, and a second current conducting electrode supplying an output current.
Claim 2
Dependent Claim
246 words
A current source circuit having a first supply voltage terminal and a second supply voltage terminal, comprising: biasing means for establishing a bias voltage comprising a first transistor having a first current conducting electrode coupled to said first supply voltage terminal, a first resistor coupled to said second supply voltage terminal, and a diode coupled between said first resistor and a second current conducting electrode of said first transistor; a second transistor having a first current conducting electrode coupled to said first supply voltage terminal; a third transistor having a control electrode coupled to said second current conducting electrode of said first transistor, a first current conducting electrode coupled to a second current conducting electrode of said second transistor, and a second current conducting electrode coupled to said second supply voltage terminal; a fourth transistor having a control electrode coupled to said first current conducting electrode of said third transistor, and a first current conducting electrode coupled to said first supply voltage terminal; a capacitor coupled between said control electrode of said third transistor and a second current conducting electrode of said fourth transistor; resistive means coupled between said second current conducting electrode of said fourth transistor and said second supply voltage terminal; and a fifth transistor having a first current conducting electrode coupled to said first supply voltage terminal, a control electrode coupled to a control electrode of both said first and said second transistor, and a second current conducting electrode supplying an output current.
References Cited (Backward Citations)
US3893017A
Cited
JPS5268946A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |