IPC 6 English version H03K !A-H03K 3/86

H03K-H03K00386

SECTION H– ELECTRICITY

H 03

BASIC ELECTRONIC CIRCUITRY

H 03 K

PULSE TECHNIQUE (measuring pulse characteristics G 01 R; mechanical counters having an electrical input G 06 M; information storage devices in general G 11; sample-and-hold arrangements in electric analogue stores G 11 C 27/02; construction of switches involving contact making and breaking for generation of pulses, e.g. by using a moving magnet, H 01 H; static conversion of electric power H 02 M; generation of oscillations by circuits employing active elements which operate in a non-switching manner H 03 B; modulating sinusoidal oscillations with pulses H 03 C, H 04 L; discriminator circuits involving pulse counting H 03 D; automatic control of generators H 03 L; starting, synchronisation, or stabilisation of generators where the type of generator is irrelevant or unspecified H 03 L; coding, decoding or code conversion, in general H 03 M) [4]

Notes

(1)

This subclass covers:

–

methods, circuits, devices, or apparatus using active elements operating in a discontinuous or switching manner for generating, counting, amplifying, shaping, modulating, demodulating, or otherwise manipulating signals;

–

electronic switching not involving contact-making and braking;

–

logic circuits handling electric pulses.

(2)

In this subclass, the following expression is used with the meaning indicated:

–

"active element" exercises control over the conversion of input energy into an oscillation or a discontinuous flow of energy.

(3)

In this subclass, where the claims of a patent document are not limited to a specific circuit element, the document is classified at least according to the elements used in the described embodiment. [6]

Circuits for generating electric pulses; Monostable, bistable or multistable circuits (H 03 K 4/00 takes precedence; for digital computers G 06 F 1/025) [5]

Details [3]

011

Modifications of generator to compensate for variations in physical values, e.g. voltage, temperature [6]

012

Modifications of generator to improve response time or to decrease power consumption [6]

013

Modifications of generator to prevent operation by noise or interference [3]

014

Modifications of generator to ensure starting of oscillations [6]

015

Modifications of generator to maintain energy constant [6]

017

Adjustment of width or dutycycle of pulses (pulse width modulation H 03 K 7/08) [3]

Generators characterised by the type of circuit or by the means used for producing pulses (H 03 K 3/64 to H 03 K 3/84 take precedence)

021

by the use, as active elements, of more than one type of element or means, e.g. BIMOS, composite devices such as IGBT [6]

023

by the use of differential amplifiers or comparators, with internal or external positive feedback [3]

0231

Astable circuits [6]

0232

Monostable circuits [6]

0233

Bistable circuits [6]

0234

Multistable circuits [6]

027

by the use of logic circuits, with internal or external positive feedback [3]

Astable circuits [3]

033

Monostable circuits [3]

037

Bistable circuits [3]

038

Multistable circuits [6]

by the use, as active elements, of vacuum tubes only, with positive feedback (H 03 K 3/023, H 03 K 3/027 take precedence) [3]

using means other than a transformer for feedback

using at least two tubes so coupled that the input of one is derived from the output of another, e.g. multivibrator

astable

Stabilisation of output [2]

monostable

bistable

Bistables with hysteresis, e.g. Schmitt trigger [6]

multistable

(transferred to H 03 K 3/13)

using a transformer for feedback, e.g. blocking oscillator with saturable core

specially adapted for amplitude comparison, i.e. Multiar

by the use, as active elements, of bipolar transistors with internal or external positive feedback (H 03 K 3/023, H 03 K 3/027 take precedence) [2]

using means other than a transformer for feedback

281

using at least two transistors so coupled that the input of one is derived from the output of another, e.g. multivibrator

282

astable

283

Stabilisation of output [2]

284

monostable

286

bistable [3]

287

using additional transistors in the feedback circuit (H 03 K 3/289 takes precedence) [3]

288

using additional transistors in the input circuit (H 03 K 3/289 takes precedence) [3]

2885

the input circuit having a differential configuration [5]

289

of the master-slave type [3]

2893

Bistables with hysteresis, e.g. Schmitt trigger [6]

2897

with an input circuit of differential configuration [6]

multistable

295

(transferred to H 03 K 3/2893)

297

(transferred to H 03 K 3/2897)

using a transformer for feedback, e.g. blocking oscillator

313

by the use, as active elements, of semiconductor devices with two electrodes, one or two potential-jump barriers, and exhibiting a negative resistance characteristic [3]

315

the devices being tunnel diodes

by the use, as active elements, of semiconductor devices exhibiting hole storage or enhancement effect

335

by the use, as active elements, of semiconductor devices with more than two electrodes and exhibiting avalanche effect

by the use, as active elements, of bipolar semiconductor devices with more than two PN junctions, or more than three electrodes, or more than one electrode connected to the same conductivity region (H 03 K 3/023, H 03 K 3/027 take precedence) [3]

351

the devices being unijunction transistors (H 03 K 3/352 takes precedence) [3]

352

the devices being thyristors [3]

3525

Anode gate thyristors or programmable unijunction transistors [6]

353

by the use, as active elements, of field-effect transistors with internal or external positive feedback (H 03 K 3/023, H 03 K 3/027 take precedence) [2,3]

354

Astable circuits [3]

355

Monostable circuits [3]

356

Bistable circuits [3]

3562

of the master-slave type [6]

3565

Bistables with hysteresis, e.g. Schmitt trigger [6]

3568

Multistable circuits [6]

357

by the use, as active elements, of bulk negative resistance devices, e.g. Gunn-effect devices [2]

by the use, as active elements, of semiconductors, not otherwise provided for [2]

by the use, as active elements, of gas-filled tubes, e.g. astable trigger circuits (H 03 K 3/55 takes precedence)

by the use, as active elements, of superconductive devices [3]

by the use, as active elements, of electrochemical cells

by the use, as active elements, of opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled

by the use, as active elements, of beam deflection tubes

by the use, as active elements, of non-linear magnetic or dielectric devices

the devices being parametrons

the devices being ferro-resonant

the devices being multi-aperture magnetic cores, e.g. transfluxors

by the use of an energy-accumulating element discharged through the load by a switching device controlled by an external signal and not incorporating positive feedback (H 03 K 3/335 takes precedence)

537

the switching device being a spark gap [3]

543

the switching device being a vacuum tube [3]

the switching device being a gas-filled tube having a control electrode

the switching device being a semiconductor device

by the use of galvano-magnetic devices, e.g. Hall-effect devices [2]

Generators producing trains of pulses, i.e. finite sequences of pulses

by interrupting the output of a generator

time intervals between all adjacent pulses of one train being equal

with means for varying repetition rate of trains

Generating a single train of pulses having a predetermined pattern, e.g. a predetermined number

Generating trains of sinusoidal oscillations (by interrupting H 03 C, H 04 L)

Generating pulses having a predetermined statistical distribution of a parameter, e.g. random pulse generators [2]

Generating pulses by means of delay lines and not covered by the preceding subgroups [2]

H03K 4/00 - H03K 5/26