Abstract: A digital control circuit with a device for generating a high-resolution tuning voltage is suitable for use in receivers for RF signals, particularly in consumer equipment. The tuning voltage can be electronically switched from one value to another at a high speed. The transient time required with conventional control loops is nearly eliminated since the low-pass filter or the digital integrator is preset to its steady-state integration value. To generate the tuning voltage, dynamic digital-to-analog convertors are provided which, despite their high resolution, require only a smoothing filter with a short response time and a short time constant.

Abstract: The adder/subtracter disclosed sums a plurality of n-digit binary-coded numbers (A, B, C . . . Z) successively by forming corresponding partial sums (Sb, Sc . . . Sz) according to the following recursive formula:A+B+C . . . +Z=((A+B)+C) . . . +Z=(Sb+C) . . . +Z=Sc . . . +Z=Sz.The partial sums are formed by means of parallel adders/subtracters which, in turn, include adder/subtracter stages. Each of the stages is formed by a full adder and a switching section which forms the ones complement of the subtrahend in case of subtraction. The inputs of the parallel adder/subtracter for the first partial sum are preceded by series-connected like delay elements beginning with the second lowest weight and increasing by one from weight to weight, the delay provided by the delay elements being equal to the time required to generate the carry of the full adder.

Abstract: In this IC set, the dark currents and the white levels of the three electron guns, the leakage currents of the cathodes, and a light-detector current are measured during four successive vertical blanking intervals. The cathode leakage currents and the dark currents are measured in the first half of the vertical blanking interval, and the light-detector current and the white-level currents are measured at the end of this interval. From these measured data and alignment data stored in a reprogrammable memory (ps), a microprocessor (mp) contained together with the memory (ps) in an integrated circuit (ic2) derives operating data for the picture tube (b) as well as further data.

Abstract: An improved digital integrated chrominance-channel circuit having gain control for color-television receivers includes at least one integrated circuit for digitally processing the composite color signal. The circuit includes a first limiter inserted between a parallel multiplier and a burst-amplitude-measuring stage, and a control stage including a parallel subtracter whose minuend input is fed with a reference signal, and whose subtrahend input is connected to the output of the burst-amplitude-measuring stage. A digital accumulator whose enable input is presented with a signal derived from the trailing edge of a burst gating signal is used as an integrator.

Abstract: In this IC set, the dark currents and the white levels of the three electron guns, the leakage currents of the cathodes, and a light-detector current are measured during four successive vertical blanking intervals. The cathode leakage currents and the dark currents are measured in the first half of the vertical blanking interval, and the light-detector current and the white level currents are measured at the end of this interval. From these measured data and alignment data stored in a reprogrammable memory (ps), a microprocessor (mp) contained together with the memory (ps) in an integrated circuit (ic2) derives operating data for the picture tube (b) as well as further data.

Abstract: A fast MOS driver circuit for digital signals having a small current consumption and a good signal-to-noise ratio comprises an output inverter, a pre-inverter and of an enhancement-type transistor having its source-drain path connected in parallel to that of the load transistor of the output inverter (IA). The gate of the enhancement-type transistor and the gates of the load transistors of the output and pre-inverters are coupled to the output of the pre-inverter. The W/L-ratio of the enhancement-type transistor is almost the same as that of the switching transistor of the output inverter. The gates of the switching transistors are connected to one another. The load transistors are of the depletion type while the switching transistors are of the enhancement type.

Abstract: Unlike prior art parallel adders, which employ conventional EXCLUSIVE-OR gates, the parallel adder disclosed uses special EXCLUSIVE-NOR gates constructed from only three transistors, so that a considerable space-saving and a reduction of power dissipation are achieved on the integrated-circuit chip. Instead of noninverted digit signals, inverted digit signals are used to form the E and D signals which are combined by means of a complex gate for each binary weight to form the inverted carry signal of this weight. This complex gate includes a number of AND elements equal to the number of the stage, and a NOR element combining the outputs of these AND elements and the D signal of this stage. The inverted carry signal of a stage and the inverted subtotal signal of the next higher-order stage are combined by means of an EXCLUSIVE-NOR gate of the above-mentioned special circuit construction to form the noninverted sum signal of the next higher order stage.

Abstract: 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.