Abstract: In an integrated circuit class B audio output device the transistors are fabricated as plural parallel connected sections. The two output transistors have their sections interdigitated so that adjacent sections are not turned on simultaneously. This leads to substantial improvements in thermal peaks within the transistors and to reduced thermal gradients across the transistors.

Abstract: A reference voltage source, in particular for amplifier circuits, includes a pair of transistors having their bases connected together, one of the transistors being further connected as a diode and the other being operated normally. In the collector circuit of the transistors, a current mirror circuit is connected which includes a further transistor which is connected in series through an additional transistor to a reference potential. The base of the additional transistor is connected with emitter resistors in the emitter circuit of the first-mentioned transistors and the reference voltage is taken off at the connection between the serially connected further and additional transistors. Additional current mirror circuits may be employed for providing a symmetrical operation of the amplifier circuit supplied by the reference voltage source.

Abstract: A bipolar transistor is utilized as the feedback element of an inverting amplifier. The base of the transistor is connected to the amplifier's output, with the emitter connected to the input thereby providing 100% voltage feedback. The output is taken across the collector load of the transistor. Signal inputs to the amplifier are coupled through conventional summing resistors. The resulting configuration is capable of high frequency operation and provides excellent isolation between input signals.

Abstract: A biasing circuit is provided for stabilizing the gain of a transistor amplifier against variations in temperature. The amplifier includes an input terminal and a transistor having a base-to-emitter junction coupled between the input terminal and the second terminal of a two-terminal source of supply potential. The biasing circuit is coupled between the two supply terminals and includes a resistor coupled to the first terminal, a semiconductor rectifying junction coupled between the input terminal of the amplifier and the second supply terminal, and the parallel combination of the collector-to-emitter path of a second transistor and a voltage divider coupled between the resistor and the rectifying junction. The base of the second transistor is coupled to an intermediate tap of the voltage divider. As the temperature of the circuit increases, the g.sub.m of the amplifying transistor decreases.

Abstract: A gain control circuit includes a first transistor with direct-coupled collector-to-base feedback converting current, applied to its collector, to logarithmically related voltage appearing between its emitter and base. This logarithmically related voltage is incremented or decremented by a voltage .DELTA.V.sub.1 proportional to T and applied to the emitter-base junction of a second transistor used as a logarithm of voltage to current converter, T being an absolute temperature close to that at which the first and second transistors are operated. .DELTA.V.sub.1 is developed as the potential drop across a resistive element R1, responsive to the output current of a current-to-logarithm-of-current converter circuit, making the conversion with a scaling factor proportional to T divided by the resistance R.sub.1 of resistive element R1. Accordingly, the gain setting of the gain control circuit is unaffected by change in T.

Abstract: A current I of predetermined temperature coefficient is supplied to the series connection of at least one semiconductor diode and a positive-temperature-coefficient resistance. This resistance is of such value that a voltage drop with a temperature-coefficient equal to that of I, in terms of percentage change per degree of temperature change, appears across the series connection. A relatively large, zero-temperature-coefficient, adjustable resistance, alone or in series with a zero-temperature-coefficient voltage source, parallels the series connection. Adjustment of the relatively large zero-temperature-coefficient resistance provides a trim for the current flow in the series connection, which trim is substantially unaffected by changing temperature.

Abstract: The base-to-emitter bias voltage and current of a high frequency transistor, operating class AB or class A, is derived from a semiconductive bias device consisting of a semiconductive diode junction fed with current from a constant current source to derive a V.sub.BE voltage thereacross which is the bias source voltage. This source voltage is applied across the base-to-emitter junction of the RF transistor via the intermediary of a positive temperature coefficient silicon resistor. The diode and silicon resistor are packaged together for mounting on a heat sink common to the transistor, whereby the transistor is compensated for temperature dependent changes in V.sub.BE and h.sub.FE.

Abstract: A temperature-compensated amplifier circuit including an amplifier section having first and second transistors which are connected at their collectors to a power source terminal through first and second resistors, and having d.c. biased bases coupled to signal source terminals; a current source including a third transistor having a collector coupled with the emitters of the first and second transistors and a grounded emitter; a fourth transistor having an emitter coupled with the power source terminal through a third resistor; a fifth transistor connected at the emitter to the power source terminal and at the base to the base of the fourth transistor; a sixth transistor having both base and collector commonly coupled to the collector of the fourth transistor and grounded at the emitter; and a seventh transistor connected at the collector to the base and the collector of the fifth transistor, at the base to the bases of the third and sixth transistors and grounded at the emitter.

Abstract: A buffer amplifier is described for use in an integrated circuit in which a siganl from a processing circuit is coupled by the buffer amplifier to an output pin on the integrated circuit. The buffer amplifier includes a pair of transistors, the first of which receives the output of the processing circuit and is preferably arranged in an emitter-follower configuration. A resistor internal to the integrated circuit is coupled between ground and the emitter of the first transistor. The second transistor, preferably a vertical PNP type transistor, is arranged in a circuit configuration to couple the output of the first transistor to the output pin and to sink any current flowing to the output pin from a circuit driven by the buffer amplifier.

Abstract: A thermal drift compensation circuit for operational amplifiers wherein a second operational amplifier is utilized to sense the error voltage between the input terminals of a first operational amplifier and generate a current therefor which compensates for errors resulting from thermal effects within the first operational amplifier.

Abstract: A ceramic capacitor with at least one semiconductor device mount hole, comprising a metal substrate and a dielectric ceramic layer provided with electrode layer on its surfaces and mounted on the substrate. At least the lateral surface of the mount hole in the electrode layer bound to the substrate is covered with an insulating material. The ceramic capacitors have good thermal conductivity and adapted to be used with semiconductor devices designed for power applications.

Abstract: A positive temperature coefficient resistance element such as a sensistor and a negative coefficient resistance element such as a thermistor are arranged in a potential divider network, the output terminal of which produces a potential which is a function of temperature. The potential is applied as a bias potential to the control electrode of an amplifier circuit subject to variations in gain as a function of both control electrode voltage and temperature to reduce the gain, as a function of temperature, of the amplifier.

Abstract: Circuitry for compensating for the effects of changes in ambient temperature on an automatic gain control arrangement in a missile-borne receiver is shown to include an operational amplifier responsive only to the level of the output signal from an automatic gain detector and amplifier, such end being effected by using temperature sensitive elements in the input and feedback circuits of the operational amplifier.

Abstract: An output transistor in common-emitter amplifier configuration is thermally coupled to means for generating a temperature-compensated component of bias potential. This bias potential is indirectly applied to the base electrode of the output transistor to provide for temperature-stabilized idling current flow in its collector-to-emitter path. More particularly, the bias potential is applied to the non-inverting terminal of a high-gain differential-input amplifier having its output terminal direct coupled to the base of the transistor and direct coupled to its inverting input terminal for regulating the quiescent potential at its output terminal to equal the bias potential. The differential-input amplifier has an input signal applied to one of its input terminals. In response to signal excursions in one sense, the differential-input amplifier drives the output transistor into increased conduction.

Abstract: A power transistor in the final stage of an IC amplifier feeding a reactive load, such as a loudspeaker, has an emitter resistor connected across the input of a monitoring transistor by way of a diode, the monitoring transistor being part of a protective circuit which reduces the input signal to the power amplifier in the event of an overload. To retard the response of the protective circuit, for the purpose of preventing signal distortions in the event of brief power surges, the diode and the monitoring transistor are so disposed on the silicon chip of the amplifier that a thermal wave from the overheating power transistor will first strike the diode, thereby reducing its resistance to compensate for an increased voltage drop across the emitter resistor, and will reach the monitoring transistor with a certain delay; if the overload persists, the resulting increase in the conductivity of the monitoring transistor re-establishes the full sensitivity of the protective circuit.

Abstract: A low frequency power amplifier uses MOS FET's each having a semiconductor device unit including a source electrode, a drain electrode and an insulated gate electrode filled in a can type casing with the source electrode being electrically connected to the can type casing. When the MOS FET having its source electrode connected to the can type casing is mounted on a heat sink and operated in a source follower configuration, a stray capacity between the can-shaped casing and the heat sink is connected in parallel with a load so that the amplifier oscillates. The heat sink is grounded through an impedance element and the stray capacity is isolated from the load to prevent the oscillation.

Abstract: An integrated circuit two terminal temperature transducer providing an accurate current output that is linearly related to absolute temperature over an extended temperature range. The circuit is of the type using first and second transistors having conductive areas of different sizes, and control transistors for supplying equal currents through the first and second transistors to operate them at different current densities, and a resistor responsive to the base-to-emitter voltages of the first and second transistors for developing currents therethrough proportional to absolute temperature. Improved accuracy over an extended temperature range is provided in a two terminal device by means of a third transistor coupled to the first and second transistors to generate another controlled current varying linearly with absolute temperature to be combined with the currents through the first and second transistors to form an output current.

Abstract: A common emitter amplifier having a resistor in series with its emitter and a resistor in series with its collector is temperature stabilized by providing a current source in parallel with the resistor in series with the collector. The current source provides additional emitter current to the transistor to decrease the transistors internal AC emitter resistance. Cascoded transistors are also used to improve the performance of the amplifier.

Abstract: A controlled current source circuit using PNP mirror transistors and having wide frequency bandwidth as well as correction for D.C. offset, said circuit comprised of first and second PNP transistors, one of which is connected as a diode, the base terminals of which are commonly connected, the collector terminals of each of which are connected respectively to first and second terminals of a current bias means providing control of emitter-base characteristics and correction for offset caused by base currents, the emitter terminals of which are each connected respectively to first and second resistors, the resistors connected to common potential source, wherein mirror currents are tapped from the connections between the emitter terminals and the resistors and wherein the output mirror current is the collector current of an NPN transistor, the base and collector terminals of which are respectively connected to the collector and emitter terminals of the second PNP transistor.

Abstract: Disclosed is a gain control circuit which comprises a gain control section including as its essential component a differential amplifier with which diodes or transistors arranged to act as diodes are connected as a load, and a control signal section including a logarithmic compression circuit and an exponential expansion circuit and providing a control signal for control of the gain of the gain control section. A temperature compensation circuit having a temperature dependence cancelling both the temperature dependence of the gain control section and that of the control signal section is provided in the bias circuit for the transistor in the last stage of the control signal section, so that the desired temperature compensation for the entire gain control circuit can be achieved at a single point.

Abstract: An amplifier circuit suitable for use as a video amplifier in a color television circuit for driving the variable impedance load provided by a color television picture tube, in which the load impedance of the amplifier element of the circuit is also made variable. This is achieved, in one embodiment by using as the output stage of the amplifier two transistors with a complementary symmetrical configuration so that one is always substantially cut-off while the other conducts. In another embodiment a transistor in common collector configuration acts as the amplifier element and its emitter from which the output of the amplifier is taken is connected by a diode to the collector of a transistor which feeds the base of the common collector transistor.

Abstract: The bias circuit of the base of an HF amplifier transistor, arranged in a common-emitter configuration, comprises an LF transistor likewise in a common-emitter configuration and two resistors respectively connecting the base of the LF transistor to its collector and to a point of fixed potential. The bias voltage varies more rapidly, as a function of temperature, than the voltage across the terminals of the reference diode formed by the base-emitter junction of the LF transistor. This permits a correct temperature compensation of the HF transistor in spite of the temperature differences between the junctions of the HF and LF transistors and of the thermal inertia of the thermal link between these two transistors.

Abstract: An electronic gain control circuit and method are disclosed for providing gain control. The gain control circuit is adaptable for use with differential amplifiers to control the gain thereof and is suitable to be fabricated in monolithic integrated circuit form. The gain control circuit utilizes voltages generated by currents established through diodes to obtain a differential gain voltage to linearly vary the gain of the amplifier. In a preferred form, the amplifier consists of first and second differentially connected transistor pairs with each pair commonly connected to a respective collector of an input differential stage. A constant current source supplies a constant current through a first diode string and is coupled to a common node between the transistor pairs for providing a fixed voltage thereat.

Abstract: The collector currents of first and second junction transistors which have base electrodes biased at the same quiescent potential and have emitter electrodes connected via respective emitter degeneration resistances to a common point, are adjusted relative to each other. This is done by applying linearly temperature-dependent voltages in adjustable ratio with each other to the emitter degeneration resistances. This makes it so that the adjustment of the relative values of the collector currents is substantially unchanging over a temperature range.