Patent US3619797A successfully refreshed from Google Patents.
US3619797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Operational amplifier
Assignee: Globe Universal Sciences Inc
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Filing: 1970-01-21
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Granted: 1971-11-09
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Expires: 1990-01-21
Abstract
Abstract A high-gain, broad bandwidth differential operational amplifier is described. High-frequency response is increased by means of a feed-forward path, which bypasses the cascaded low-frequency differential stages at high frequencies and feeds the signal directly to a common base cascade output stage so that the rolloff of the low-frequency cascaded stages does not affect the high-frequency response of the amplifier.
Inventors
- 👤 James W Merrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:42
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/42; H03F1/48; H03F1/08; H03F1/22; H03F1/223; H03F3/00; H03F3/30; H03F3/3069; H03F3/3071; H03F3/45; H03F3/45071; H03F3/45076; H03F3/4508; H03F3/45085; H03F3/45089; H03F3/45479; H03F3/45484; H03F3/45488; H03F3/45493; H03F3/45502; H03F2203/00; H03F2203/45; H03F2203/45406; H03F2203/45466; H03F2203/45498; H03F2203/45686; H03F2203/45702; H03F2203/45716
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
159 words
An operational amplifier circuit, comprising: a plurality of differential amplifier stages connected in cascade with each other; a feed-forward path connected to the input of said plurality of differential amplifier stages, said feed-forward path including a high-pass filter network; a high-frequency amplifier stage connected in said feed-forward path to the output of said high-pass filter network, said highfrequency amplifier stage comprising a field effect transistor connected in grounded source configuration; a first output transistor connected to the output of said field effect transistor and being disposed in grounded base configuration; a second output transistor connected to the output of the last of said differential amplifier stages, said second output transistor being disposed in grounded base configuration; at least one diode connected between the collector of said first output transistor and the collector of said output transistor; a complementary emitter follower stage connected across said diode, whereby a single-ended output signal may be derived from said complementary emitter follower circuit.
Claim 2
Dependent Claim
159 words
An operational amplifier circuit, comprising: a plurality of differential amplifier stages connected in cascade with each other; a feed-forward path connected to the input of said plurality of differential amplifier stages, said feed-forward path including a high-pass filter network; a high-frequency amplifier stage connected in said feed-forward path to the output of said high-pass filter network, said highfrequency amplifier stage comprising a field effect transistor connected in grounded source configuration; a first output transistor connected to the output of said field effect transistor and being disposed in grounded base configuration; a second output transistor connected to the output of the last of said differential amplifier stages, said second output transistor being disposed in grounded base configuration; at least one diode connected between the collector of said first output transistor and the collector of said output transistor; a complementary emitter follower stage connected across said diode, whereby a single-ended output signal may be derived from said complementary emitter follower circuit.
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) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |