Itt Industries, Inc.

Dieter Holzmann

Dirk Hoffmeister

Albrecht Gerlach

Herbert Elmis

Friedrich Schmidtpott

Wolfgang Gollinger

Hermannus Schat

Daniel Mlynek

Joachim Grosse

Guenter Lindstedt

Detlev Kunz

Holger Struthoff

Rolf-Dieter Burth

To adjust time delays in equidistant steps, an inverter chain is provided with an even number of static inverters of identical topology. The output of one of the even-numbered inverters is connected to the signal output via a selector switch. During suitable frequency-measuring periods, an odd number of inverters is connected to form a ring by directly coupling the output of an odd-numbered inverter to the input of the first, and a digital measuring arrangement determines the time delay of the ring-connected portion from the frequency of the ring's self-excited oscillation. The output signal of the measuring arrangement is used to adjust the time delay of the inverter chain.

MOSFET Integrated delay circuit for digital signals and its use in

A binary-to-decimal code converter consists of matrix-like arranged MOS transistors connected in series and parallel to each other in order to enable the optimum space arrangement on the chip.

MOS-Binary-to-decimal code converter

A keyboard switch matrix has a plurality of column and row wires and switches having only two poles and no interconnecting diodes for selectively connecting one of said columns to one of said rows. Associated with each column and row wire is a flip-flop having a set input connected to the wire and an electronic switch for each flip-flop connecting a flip-flop output to the set input. The outputs of the row flip-flops are connected to a NOR-gate, the output of which is connected to a control input of the electronic switches associated with the column flip-flops and also to a second set input of the column flip-flops. The output of the NOR-gate is further connected to a control input of the electronic switches associated with the row flip-flops through an inverter. Reset inputs of the column flip-flops are connected to the NOR-gate output through a differentiation circuit which is triggered by a negative pulse edge. A second NOR-gate has its inputs connected to the column wires and provides an output to a differentiation circuit which is triggered by a positive pulse edge. The output of the differentiation circuit is connected to reset inputs of the row flip-flops. Thus, the geometric position of the actuated keyboard switch is stored in the respective row and column flip-flops, and code signals corresponding to said position are provided at the outputs of said flip-flops.

Circuit arrangement for an input keyboard

A remote control arrangement uses pulse code modulation for transmission as in infrared remote control arrangements. A feature of the arrangement is that only one quartz oscillator is necessary and is used in the receiver part. The receiver measures the first pulse width transmitted and, dependent on that, defines the measured period of a control circuit. A primary feature is that the arrangement is provided with a prepulse having a threefold pulse width before the start pulse thereby allowing the preamplifier of the receiver to be in its normal operating area when the start pulse occurs.

Remote control arrangement using pulse spacing modulator

This invention concerns a monolithical integrated organ gate circuit showing a load resistance common to all audio signal currents. For the suppression of any bounces possibly occurring upon the operation of a second key after a first one, there is a rest current coordinated to each audio signal current which rest current is fed to the load resistance when the related key is not operated and which rest current amounts to the mean value of the related audio signal current.

Monolithic integrated organ gate circuit

The circuit enables the selection of the upper or the lower tone of an electronic organ chord with regard to a switching signal. In response to said switching signal each tone frequency signal handled is either fed to the anode or the cathode of a switch component of a plurality of switch components connected in series whereas the switch components of the tone frequency signal not handled are switched on.

Monolithic integrated selection circuit

The invention discloses a method and apparatus for digitally generating a variable pulse train with some pulses in a period T, the number of which can be changed step by step. The pulse train can be used for generating a variable dc voltage particularly for the tuning voltage of TV receiver capacitance diodes.

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Freiburg-Munzingen, Germany

Dieter Holzmann