← Back to Patent Explorer
US4123670A Expired / Lapsed US ⏱️ 0.0 years remaining

Transistor switching circuit

Assignee: Wincor Nixdorf International GmbH
•
Filing: 1976-12-06
•
Granted: 1978-10-31
•
Expires: 1996-12-06
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A transistor switching circuit arrangement for switching at least one switching transistor on and off wherein, in order to achieve low power dissipation by delaying the change which occurs in base current to the cut-off value on conversion into the blocked state and by a subsequent brief disruptive operation of the base emitter section and in order to achieve fast switching on, there is provided a choke coil through part of which the base-emitter current of said switching transistor is fed and through part of which the current being switched is passed in positive feedback mode.

Inventors

  • 👤 Werner Pollmeier

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 04:03
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/53; H02M7/537; H02M7/538; H02M7/5381; H02M1/00; H02M1/08; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/337; H02M3/3372; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/1555; H02M7/21; H02M7/217; H02M7/2173; H03; H03K; H03K17/00; H03K17/04; H03K17/042; H03K17/0424; H03K17/51; H03K17/56; H03K17/60; H03K17/601

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 142 words
A transistor switching circuit arrangement for switching at least one switching transistor on and off, said circuit arrangement having means for achieving low power dissipation by delaying the change which occurs in base current to the cut-off valve on conversion into the blocked state and by a subsequent brief disruptive operation of the base emitter section and also for achieving fast switching for the transistor by increasing the base current occurring at the time of switching on, said means comprising a choke coil connected between the base circuit of said transistor and a subsequent point through which part of the base-emitter current of said switching transistor is fed and also connected in part between the emitter of said transistor and said subsequent point, wherein the collector-emitter current being switched is passed through said part of the choke coil in positive feedback mode.
Claim 2
Dependent Claim 142 words
A transistor switching circuit arrangement for switching at least one switching transistor on and off, said circuit arrangement having means for achieving low power dissipation by delaying the change which occurs in base current to the cut-off valve on conversion into the blocked state and by a subsequent brief disruptive operation of the base emitter section and also for achieving fast switching for the transistor by increasing the base current occurring at the time of switching on, said means comprising a choke coil connected between the base circuit of said transistor and a subsequent point through which part of the base-emitter current of said switching transistor is fed and also connected in part between the emitter of said transistor and said subsequent point, wherein the collector-emitter current being switched is passed through said part of the choke coil in positive feedback mode.
Claim 3
Dependent Claim 23 words
An arrangement as defined in claim 1 wherein a parallel resistor-capacitor circuit is connected in series with the base of the switching transistor.
Claim 4
Dependent Claim 30 words
An arrangement as defined in claim 1, wherein there is inserted in the connection to the base of the switching transistor a parallel circuit comprising a capacitor and a diode.
Claim 5
Dependent Claim 32 words
An arrangement as defined in claim 1, wherein there is inserted in the connection to the base of the switching transistor a parallel circuit comprising a capacitor and a source of potential.
Claim 6
Dependent Claim 20 words
An arrangement as defined in claim 1 wherein a damping resistor is connected in parallel with the said choke coil.
Claim 7
Dependent Claim 42 words
An arrangement as defined in claim 1 wherein a bipolar base control voltage is applied to the circuit arrangement via a control repeating coil and the secondary side of a full-wave rectifier, said rectifier having a primary side and a secondary side.
Claim 8
Dependent Claim 18 words
An arrangement as defined in claim 6 wherein the full-wave rectifier comprises diodes as the active elements therein.
Claim 9
Dependent Claim 20 words
An arrangement as defined in claim 6 wherein the full-wave rectifier comprises auxiliary switching transistors as the active elements therein.
Claim 10
Dependent Claim 32 words
An arrangement as defined in claim 6 wherein the output voltage from the full-wave rectifier is applied to the base of the switching transistor via the emitter-collector circuit of an auxiliary transistor.
Claim 11
Dependent Claim 32 words
An arrangement as defined in claim 7 wherein the output voltage from the full-wave rectifier is applied to the base of the switching transistor via the emitter-collector circuit of an auxiliary transistor.
Claim 12
Dependent Claim 78 words
A push pull circuit arrangement as defined in claim 1 for switching the switching transistors of a push pull converter wherein there is provided, in the circuitry of each switching transistor a choke coil part of which is connected to the base current circuit of the other switching transistor via a diode of such polarity of connection that, during switching off of said switching transistor a potential blocking the other switching transistor is applied to the base thereof.
Claim 13
Dependent Claim 58 words
An arrangement as defined in claim 11 wherein the two choke coils are cross-connected to each other via the diodes and each has one tap connected to a point of reference potential and a second tap connected to the emitter of the switching transistor the base current of which flows through part of the choke coil in question.

References Cited (Backward Citations)

CA692368A Cited
US2933642A Cited
US3040269A Cited
US3569742A Cited
US3805094A Cited
US3983418A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-30 1982-05-01 1982-10-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-30 1986-05-01 1986-10-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-30 1990-05-01 1990-10-31 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag