US3919656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-efficiency tuned switching power amplifier
Assignee: Individual
•
Filing: 1973-04-23
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Granted: 1975-11-11
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Expires: 1993-04-23
Abstract
Abstract A high efficiency tuned switching power amplifier employs an active device switch driven at a frequency determined by an a.c. input signal. The active device switch controls the application of direct current power to a load through a resonant load network. The load network is substantially nonresistive and its resonance minimizes power loss by insuring that in the transition of the switch from ''''on'''' to ''''off,'''' the voltage across the switch remains low (viz. substantially zero) until the current through the switch has fallen to zero (viz. current flow ceases). The network, in addition, insures that the voltage across the switch is zero at the end of the off state so that current flow through the switch recommences when there is substantially zero voltage across the switch and that that voltage remains substantially zero while current flow through the switch continues. The network further causes the voltage waveform across the switch to have zero or nearly zero time derivative at the end of the off state.
Inventors
- 👤 Nathan O Sokal
- 👤 Alan D Sokal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:01
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/20; H03F3/21; H03F3/217; H03F3/2176
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
287 words
In apparatus of the tuned switching type for the highefficiency generation of alternating-current power, having A. an active device switch having a low-impedance on state and a high-impedance off state, B. driver means for causing the switch to commute periodically between the two states, C. a load network having an input port and an output port, said input port being connected in series with the switch, D. a load coupled to the output port of the load network, and E. means for supplying D.C. power to the series combination of the switch and the load network input port, the aforementioned elements being connected such that an inductive element is disposed in the D.C. path which extends to the switch from the means for supplying the D.C. power, and wherein the subcombination of the load network and the load includes F. A damped resonant circuit, operative at least while the switch is in the off state, in which the damping is effected at least in part by the resistance of the load, said damped resonant circuit including 1. at least one capacitive element whose capacitive reactance at the operating frequency is apprecIable, and 2. at least one inductive element whose inductive susceptance at the operating frequency is appreciable, the improvement wherein the values of the elements in the subcombination of the load and the load network are such that the voltage across the switch is substantially zero at the end of the off state, the voltage across the switch is substantially zero during the time the switch is in transition from the off state to the on state, and the time derivative of the voltage across the switch is substantially zero at the end of the off state.
Claim 2
Dependent Claim
287 words
In apparatus of the tuned switching type for the highefficiency generation of alternating-current power, having A. an active device switch having a low-impedance on state and a high-impedance off state, B. driver means for causing the switch to commute periodically between the two states, C. a load network having an input port and an output port, said input port being connected in series with the switch, D. a load coupled to the output port of the load network, and E. means for supplying D.C. power to the series combination of the switch and the load network input port, the aforementioned elements being connected such that an inductive element is disposed in the D.C. path which extends to the switch from the means for supplying the D.C. power, and wherein the subcombination of the load network and the load includes F. A damped resonant circuit, operative at least while the switch is in the off state, in which the damping is effected at least in part by the resistance of the load, said damped resonant circuit including 1. at least one capacitive element whose capacitive reactance at the operating frequency is apprecIable, and 2. at least one inductive element whose inductive susceptance at the operating frequency is appreciable, the improvement wherein the values of the elements in the subcombination of the load and the load network are such that the voltage across the switch is substantially zero at the end of the off state, the voltage across the switch is substantially zero during the time the switch is in transition from the off state to the on state, and the time derivative of the voltage across the switch is substantially zero at the end of the off state.
Claim 3
Dependent Claim
94 words
at least one inductive element whose inductive susceptance at the operating frequency is appreciable, the improvement wherein the values of the elements in the subcombination of the load and the load network are such that the voltage across the switch is substantially zero at the end of the off state, the voltage across the switch is substantially zero during the time the switch is in transition from the off state to the on state, and the time derivative of the voltage across the switch is substantially zero at the end of the off state.
Claim 4
Dependent Claim
94 words
at least one inductive element whose inductive susceptance at the operating frequency is appreciable, the improvement wherein the values of the elements in the subcombination of the load and the load network are such that the voltage across the switch is substantially zero at the end of the off state, the voltage across the switch is substantially zero during the time the switch is in transition from the off state to the on state, and the time derivative of the voltage across the switch is substantially zero at the end of the off state.
Claim 5
Dependent Claim
75 words
The improvement according to claim 1, further characterized in that the combination of the load network and the load includes a circuit which is substantially an impedance-transform of the following circuit: disposed in parallel in the A.C. path across the switch are a first branch and a second branch, A. the first branch comprising the series combination of i. a resistive element of resistance R at the operating frequency, ii. an inductive element of inductance
Claim 6
Dependent Claim
85 words
The improvement according to claim 1, further characterized in that the switch ''''on'''' duty ratio is substantially 50%, and that the subcombination of the load network and the load includes a circuit which is substantially an impedance-transform of the following circuit: disposed in parallel in the A.C. path across the switch are a first branch and a second branch, A. the first branch comprising the series combination of i. a resistive element of resistance R at the operating frequency, ii. an inductive element of inductance
Claim 7
Dependent Claim
32 words
The improvement according to claim 1, wherein the A.C. input admittance of the subcombination of the load network and the load, measured at the input port of the load network, is substantially
Claim 8
Dependent Claim
29 words
The improvement according to claim 4 wherein the switch on duty ratio is substantially 50% and a. x is defined as 1+1/QL, and b. y is defined as (1+1/QL)/6.3.
Claim 9
Dependent Claim
85 words
The improvement according to claim 1 wherein the load network further includes means for storing electric charge, said means being disposed in the A.C. path across the active device switch, and the element values in the subcombination of the network load and the load are further such that when the switch is in transition from the on state to the off state, any substantial increase in voltage across the switch is delayed at least until the current through the switch has fallen to substantially zero.
Claim 10
Dependent Claim
75 words
The improvement according to claim 6, further characterized in that the combination of the load network and the load includes a circuit which is substantially an impedance-transform of the following circuit: disposed in parallel in the A.C. path across the switch are a first branch and a second branch, A. the first branch comprising the series combination of i. a resistive element of resistance R at the operating frequency, ii. an inductive element of inductance
Claim 11
Dependent Claim
85 words
The improvement according to claim 6, further characterized in that the switch on duty ratio is substantially 50%, and that the subcombination of the load network and the load includes a circuit which is substantially an impedance-transform of the following circuit: disposed in parallel in the A.C. path across the switch are a first branch and a second branch, A. the first branch comprising the series combination of i. a resistive element of resistance R at the operating frequency, ii. an inductive element of inductance
Claim 12
Dependent Claim
32 words
The improvement according to claim 6, wherein the A.C. input admittance of the subcombination of the load network and the load, measured at the input port of the load network, is substantially
Claim 13
Dependent Claim
29 words
The improvement according to claim 9 wherein the switch on duty ratio is substantially 50% and a. x is defined as 1+1/QL, and b. y is defined as (1+1/QL)/6.3.
References Cited (Backward Citations)
US3437931A
Cited
US3430157A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |