US4233529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistors power stages
Assignee: BRITISH ELECTRONIC PRODUCTS (1948) Ltd
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Filing: 1978-02-22
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Granted: 1980-11-11
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Expires: 1998-02-22
Abstract
Abstract In circuitry comprising a switching power output transistor stage and a driver transistor circuit, energy is stored in a magnetic circuit during the transistor on time to provide the turn off current. First and second magnetically coupled inductors are connected in series on the output of the driver transistor, and the base of the power transistor is connected to the junction point of the two series inductors. One or more diodes are connected in parallel with the first inductor to limit the potential drop across this inductor at turn on, and a parallel combination of at least one diode and a resistor is connected in series with the second inductor. The output stage may be two power transistors connected in a Darlington type configuration with a similar inductive circuit provided for each transistor.
Inventors
- 👤 Reginald H. Whitlock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:50
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/60; H03K17/601; H03K17/04; H03K17/041; H03K17/0412; H03K17/04126; H03K17/12; H03K17/64
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
107 words
A transistor power switching stage and driver circuit comprising a driver transistor having first and second output electrodes and a control electrode, a power transistor having first and second output electrodes and a control electrode, a switching control circuit connected to the control electrode of said driver transistor, first and second magnetically coupled inductors connected in series electrically to said second output electrode of said driver transistor, a connection between the junction of said series-connected inductors and the control electrode of said power transistor, and at least one diode connected between said second output electrode of said driver transistor and said control electrode of the power transistor.
Claim 2
Dependent Claim
107 words
A transistor power switching stage and driver circuit comprising a driver transistor having first and second output electrodes and a control electrode, a power transistor having first and second output electrodes and a control electrode, a switching control circuit connected to the control electrode of said driver transistor, first and second magnetically coupled inductors connected in series electrically to said second output electrode of said driver transistor, a connection between the junction of said series-connected inductors and the control electrode of said power transistor, and at least one diode connected between said second output electrode of said driver transistor and said control electrode of the power transistor.
Claim 3
Dependent Claim
31 words
Circuitry according to claim 1, wherein the second inductor is connected to a driver transistor supply line in series with a parallel combination of at least one diode and a resistor.
Claim 4
Dependent Claim
22 words
Circuitry according to claim 2, wherein an oppositely poled diode is connected in parallel with the second inductor and said parallel combination.
Claim 5
Dependent Claim
27 words
Circuitry according to claim 1 or claim 2 or claim 3, wherein the inductors have the same number of turns and are wound on powdered core material.
Claim 6
Dependent Claim
47 words
Circuitry according to claim 1 or claim 2 or claim 3, wherein a second power transistor is connected to the first in Darlington configuration, the same inductive circuit arrangements being provided between the two Darlington connected transistors as between the first such transistor and the driver transistor.
Claim 7
Dependent Claim
88 words
Circuitry according to claim 2, wherein a second power transistor is connected to the first in Darlington configuration, a third inductor is connected in series between the output electrode of the driver transistor and the first inductor, a fourth inductor is connected between an output electrode of said first power transistor and said supply line, and the number of turns in the third inductor is greater than the number of turns in the fourth inductor by a factor substantially equal to the gain of the first power transistor.
Claim 8
Dependent Claim
36 words
Circuitry according to claim 6, wherein a diode is provided in parallel with said third inductor, and a parallel combination of one or more diodes and a resistor is provided in series with said fourth inductor.
Claim 9
Dependent Claim
40 words
Circuitry according to claim 1, further comprising a flywheel diode in parallel with a load connected to the first output electrode of the power transistor, and a load inductor in series with said load to limit the turn on current.
Claim 10
Dependent Claim
17 words
Circuitry according to claim 8, wherein a diode circuit is provided in parallel with the load inductor.
Claim 11
Dependent Claim
34 words
Circuitry according to claim 8, wherein a snubber network, comprising a resistor, capacitor and diode, is connected across the output electrodes of the power transistor to control the locus of operation during turn off.
Claim 12
Dependent Claim
35 words
Circuitry according to claim 8 or claim 10, wherein an overwinding is provided on said load inductor having a much larger number of turns and connected in series with a diode across the load supply.
Claim 13
Dependent Claim
116 words
A transistor power switching stage and driver circuit comprising a driver transistor having first and second output electrodes and a control electrode, a power transistor having first and second output electrodes and a control electrode, a switching control circuit connected to the control electrode of said driver transistor, first and second magnetically coupled inductors connected in series electrically to said second output electrode of said driver transistor, a connection between the junction of said series-connected inductors and the control electrode of said power transistor, and at least one diode connected between said second output electrode of said power transistor and end terminal of said series-connected inductors remove from said second output electrode of said driver transistor.
Claim 14
Dependent Claim
116 words
A transistor power switching stage and driver circuit comprising a driver transistor having first and second output electrodes and a control electrode, a power transistor having first and second output electrodes and a control electrode, a switching control circuit connected to the control electrode of said driver transistor, first and second magnetically coupled inductors connected in series electrically to said second output electrode of said driver transistor, a connection between the junction of said series-connected inductors and the control electrode of said power transistor, and at least one diode connected between said second output electrode of said power transistor and end terminal of said series-connected inductors remove from said second output electrode of said driver transistor.
References Cited (Backward Citations)
US3666971A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-11 | 1984-05-12 | 1984-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-11 | 1988-05-12 | 1988-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-11 | 1992-05-12 | 1992-11-11 | $7700.00 | Window Closed / Lapsed |