Patent US668514A successfully refreshed from Google Patents.
US3320439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-value current source for integrated circuits
Assignee: Fairchild Semiconductor Corp
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Filing: 1965-05-26
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Granted: 1967-05-16
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Expires: 1985-05-26
Abstract
No abstract record available.
Inventors
- 👤 Robert J Widlar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:41
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/30
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
63 words
A CURRENT SOURCE COMPRISING: A COMMON TERMINAL; A RESISTOR COUPLED TO SAID COMMON TERMINAL; AND A PAIR OF TRANSISTORS OPERATIVELY COUPLED TO APPLY THE DIFFERENCE BETWEEN THEIR BASE-EMITTER VOLTAGES AS SUBSTANTIALLY THE ENTIRE VOLTAGE ACROSS SAID RESISTOR, WHEREBY THE SMALL PREDICTABLE DIFFERENCE IN THESE VOLTAGES ENABLES RESISTORS LESS THAN APPROXIMATELY 10K OHMS TO BE EMPLOYED TO SUPPLY OUTPUT CURRENTS LESS THAN 20 MICROAMPERS.
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) | 1970-05-15 | 1970-11-14 | 1971-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-05-15 | 1974-11-14 | 1975-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-05-15 | 1978-11-14 | 1979-05-16 | $7700.00 | Window Closed / Lapsed |