Patent US2620669A successfully refreshed from Google Patents.
Patent US3714466A successfully refreshed from Google Patents.
US3714466A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Clamp circuit for bootstrap field effect transistor
Assignee: Boeing North American Inc
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Filing: 1971-12-22
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Granted: 1973-01-30
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Expires: 1991-12-22
Abstract
Abstract A clamp field effect transistor is connected between the gate electrode of a bootstrap driver circuit and a voltage level. The clamp becomes responsive to voltage levels fed-back to the gate electrode of said driver circuit for clamping the voltage on the gate electrode to a level which holds the driver circuit off when the output voltage level from the driver circuit becomes approximately equal to the first voltage level. As a result, the voltage level at the output of the driver circuit can be increased in magnitude for providing a relatively higher voltage for driving other circuits.
Inventors
- 👤 J Spence
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:53
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/01; H03K19/017; H03K19/01707; H03K19/01714
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
133 words
A clamp circuit for a bootstrap field effect transistor driver including feedback capacitor between the output and gate electrode of the field effect transistor driver and a field effect transistor connected between a voltage source and the gate electrode of said bootstrap field effect transistor driver for precharging the feedback capacitor to a voltage level sufficient to turn said bootstrap field effect transistor driver on, said clamp circuit comprising, a clamping field effect transistor connected between the gate electrode of said bootstrap field effect transistor driver and said voltage source for responding to voltage levels feedback to the gate electrode of said bootstrap field effect transistor driver across said feedback capacitor, said clamping field effect transistor clamping said gate electrode to a voltage level for turning said bootstrap field effect transistor driver off.
Claim 2
Dependent Claim
133 words
A clamp circuit for a bootstrap field effect transistor driver including feedback capacitor between the output and gate electrode of the field effect transistor driver and a field effect transistor connected between a voltage source and the gate electrode of said bootstrap field effect transistor driver for precharging the feedback capacitor to a voltage level sufficient to turn said bootstrap field effect transistor driver on, said clamp circuit comprising, a clamping field effect transistor connected between the gate electrode of said bootstrap field effect transistor driver and said voltage source for responding to voltage levels feedback to the gate electrode of said bootstrap field effect transistor driver across said feedback capacitor, said clamping field effect transistor clamping said gate electrode to a voltage level for turning said bootstrap field effect transistor driver off.
Claim 3
Dependent Claim
133 words
A clamp circuit for a bootstrap field effect transistor driver including feedback capacitor between the output and gate electrode of the field effect transistor driver and a field effect transistor connected between a voltage source and the gate electrode of said bootstrap field effect transistor driver for precharging the feedback capacitor to a voltage level sufficient to turn said bootstrap field effect transistor driver on, said clamp circuit comprising, a clamping field effect transistor connected between the gate electrode of said bootstrap field effect transistor driver and said voltage source for responding to voltage levels feedback to the gate electrode of said bootstrap field effect transistor driver across said feedback capacitor, said clamping field effect transistor clamping said gate electrode to a voltage level for turning said bootstrap field effect transistor driver off.
Claim 4
Dependent Claim
133 words
A clamp circuit for a bootstrap field effect transistor driver including feedback capacitor between the output and gate electrode of the field effect transistor driver and a field effect transistor connected between a voltage source and the gate electrode of said bootstrap field effect transistor driver for precharging the feedback capacitor to a voltage level sufficient to turn said bootstrap field effect transistor driver on, said clamp circuit comprising, a clamping field effect transistor connected between the gate electrode of said bootstrap field effect transistor driver and said voltage source for responding to voltage levels feedback to the gate electrode of said bootstrap field effect transistor driver across said feedback capacitor, said clamping field effect transistor clamping said gate electrode to a voltage level for turning said bootstrap field effect transistor driver off.
Claim 5
Dependent Claim
121 words
The clamp circuit recited in claim 1 wherein said clamping field effect transistor has its gate electrode connected to the gate electrode of said bootstrap field effect transistor driver for becoming conductive when the voltage level on the gate electrode exceeds the voltage level of the voltage source by an amount equal to the threshold voltage of said clamping field effect transistor, said threshold voltage being less than the threshold voltage of said bootstrap field effect transistor driver whereby said boot-strap field effect transistor driver is turned off and the voltage level on the output electrode continues to increase to its maximum value without being clamped to the voltage level of the voltage source through said bootstrap field effect transistor driver.
Claim 6
Dependent Claim
47 words
The clamp circuit recited in claim 1 wherein said clamping field effect transistor has its gate electrode and one other electrode connected at a common point to the gate electrode of said bootstrap field effect transistor driver and having its other electrode connected to said voltage source.
Claim 7
Dependent Claim
82 words
The clamp circuit recited in claim 3 wherein said clamping field effect transistor is relatively wider than the bootstrap field effect transistor driver for having a lower threshold voltage, said lower threshold voltage enabling said clamping field effect transistor to clamp the gate electrode of said bootstrap field effect transistor to a voltage level which is insufficient to provide a threshold voltage difference between said voltage source and the voltage level on said gate electrode of said bootstrap field effect transistor driver.
Claim 8
Dependent Claim
49 words
The clamp circuit recited in claim 4 wherein said bootstrap field effect transistor driver is connected in series with a second field effect transistor for forming an inverter circuit, said output taken at a common point between said bootstrap field effect transistor driver and said second field effect transistor.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |