Abstract: A microwave oven includes an inverter inducing a high frequency oscillating current at a primary winding of a transformer via a switching element turned on and off, a magnetron to which a high voltage is applied by the transformer, a temperature sensor sensing the temperature of heat generated by the switching element to thereby generate a temperature signal, and a microcomputer compensating "on" and "off" periods of the switching element in response to the temperature signal from the temperature sensor so that an increase in an amount of an anode current in the magnetron is restrained with an increase of the temperature sensed by the temperature sensor. The microcomputer also functions to deenergize the switching element when the temperature of the switching element sensed by the temperature sensor exceeds a predetermined value.

Abstract: A positive temperature coefficient current source having reduced reference current requirements. The output transistors are each buffered by another transistor in a Darlington pair configuration. The reference current required for the circuit is reduced while maintaining a positive temperature coefficient for the current source.

Abstract: A temperature-compensated voltage generating circuit suited for an output stage of a logical circuit is provided. The voltage generating circuit includes a bipolar transistor, a first resistor connected between the collector and the base of the bipolar transistor and a series circuit including a second resistor and a Schottky barrier diode and connected between the base and the emitter of the bipolar transistor. The temperature dependency of the base-emitter forward voltage of the bipolar transistor is offset by the temperature dependency of the forward voltage of the Schottky barrier diode by having the ratio of the resistances of the first and second resistors set based on a predetermined formula.

Abstract: A combined CMOS/linear circuit employs a voltage reference circuit to provide a temperature compensated V.sub.REF output. The circuit includes means for switching the reference circuit off and on in response to the signal on an enable terminal. The voltage reference circuit includes a current mirror feedback which is positive in nature to provide a controlled hysteresis action. This provides noise immunity for the enable input. A digital output indicator is included to indicate the state of the reference circuit.

Abstract: In solid state relay circuit including a metal oxide field effect transistor connected for switching current to a load circuit, a latch circuit including first and second transistors connected to monitor a voltage caused by current in the load circuit and to shunt current away from the field effect transistor in response to current overload in the load circuit, the first and second transistors having temperature characteristics such that they turn on in response to different voltages at different temperatures, the improvement including a second means for turning on the latch to shunt current away from the field effect transistor in response to the voltage caused by current in the load circuit, the second apparatus including temperature compensating apparatus for matching the temperature characteristics of the first and second transistors of the latch circuit whereby the latch turns on at the same voltage in the load circuit over the typical operating range of the device.

Abstract: A circuit configuration for monitoring the temperature of power switching transistor integrated in a semiconductor circuit for overload protection includes temperature sensors each being associated with one respective power switching transistor for detecting the circuit temperature and issuing an output signal. Comparison stages are each connected to a respective one of the temperature sensors for comparing the output signal of one of the temperature sensors with a first reference corresponding to a first predetermined temperature value and switching off only the power switching transistor associated therewith upon attainment of the first predetermined temperature value.

Abstract: This voltage reference circuit has high thermal stability and minimal bulk and comprises a transistor defining a base-emitter junction having a voltage drop which varies in a non-linear manner as a function of temperature and resistors connected in series to the junction, the junction and the resistors being interposed between a ground line and the output terminal. A compensation transistor generates a compensation current which varies as a function of temperature so as to produce a voltage drop with a behavior substantially opposite to the previous voltage drop upon reaching the switching on temperature of the transistor.

Abstract: Practical structures of an ultra large scale semiconductor integrated (ULSI) circuit especially a dynamic random access memory of 16 M bits or more are involved. The ULSI circuit uses internal operating voltages and how to construct a reference voltage generating circuit and a voltage limiter circuit in the ULSI circuit is a matter of importance. The operation of the reference voltage generating circuit and voltage limiter circuit can be stabilized, characteristics of these circuits are improved, and layout of these circuits as applied to memory cell array, peripheral circuits and the like can be improved. Improved methods of testing these circuits are provided.

Abstract: A solid-state electrical circuit (10) includes a reference diode (D1) and multiple diodes (D3-D14) connected in electrical series to produce a substantially temperature-invariant output reference voltage. The reference diode is characterized by a forward voltage drop (V.sub.D1) that changes in accordance with a temperature coefficient. The multiple diodes, which have selected junction areas (A1 and A2) and receive one of two different forward-bias currents (I1 and I2), are electrically interconnected to establish a net voltage (.DELTA.V.sub.Di) that equals the forward voltage drop across the reference diode and changes in accordance with a net temperature coefficient of substantially equal magnitude but of opposite sign to the temperature coefficient of the reference diode. The output reference voltage equals the sum of the forward voltage drop across the reference diode and the net voltage established by the multiple diodes.

Abstract: A reference voltage developing circuit that develops a multiple slope reference voltage that is a function of temperature. The circuit has a plurality of base-emitter multipliers each of which includes a transistor and each of which develops an output voltage that is a function of the base-emitter voltage of the transistor of the multiplier. Since the base-emitter voltage varies with changes in temperature, each multiplier circuit develops a voltage that varies with changes in temperature. The multiplier circuits have different multiplier magnitudes to thereby provide temperature dependent output voltages that have different slopes. A voltage selector circuit is connected to the multiplier circuits and it provides an output voltage that corresponds to the higher of the output voltages developed by the multiplier circuits.

Abstract: A circuit for compensating for MOS device response to supply voltage variations, as well as temperature and process variations, in an integrated circuit device. The compensation circuit produces a reference voltage which modulates the gate bias voltage of a MOS transistor such that the gate-to-source bias of the MOS transistor is varied to compensate for variations in the supply voltage as well as for variations in the temperature and manufacturing process. The circuit pulls up the reference voltage toward the supply voltage as the supply increases, thereby increasing the gate drive on the MOS transistor. The circuit provides compensation for both AC and DC supply variations. The MOS transistor is used to modulate the available current sinking capability in an IC device output buffer, such that as the MOS gate drive increases, the current sinking capability is reduced, thereby slowing the output state transitions as the supply increases, and reducing noise caused by supply variations.

Abstract: A bias current supply circuit (20) is provided which includes an initial current source comprising a FET (22) coupled to a current mirror circuit comprising a pair of BJTs (26 and 28). An active resistive element comprising a second FET (24) is included to stabilize an output current I.sub.O with respect to ambient temperature variations and process variations.

Abstract: An emitter coupled logic (ECL)-to-complementary metal-oxide-semiconductor (CMOS) logic level translator is temperature compensated to track temperature induced shifts in the ECL logic levels. The translator includes a differential amplifier with mid-range reference voltage. A reference voltage generator supplies the reference voltage to the differential amplifier and has a temperature sensitive transistor which changes the value of the circuit output (reference) voltage ambient with temperature shifts.

Abstract: A device for regulating delivery of power from an AC voltage source to a load such as a lamp, a motor, a heating element or the like is described. Electronic circuitry responsive to the AC voltage generates a periodic signal whose magnitude indicates the instantaneous phase angle of the AC voltage relative to the most recent zero crossover of the AC voltage throughout the entirety of each half cycle of operation. A comparator generates a triggering signal when the phase angle signal corresponds to a threshold signal which may be manually set by adjustment of a voltage divider or which may be generated by a sensor in response to a predetermined condition, such as ambient light level or temperature, which is to be regulated by appropriate delivery of power to the load. The triggering signal is applied to a triac series connected with the load to initiate conduction of load current.

Abstract: This variable-current source comprises a differential stage and a pair of voltage buffers which respectively receive, at the input, a variable input voltage and a reference voltage and are connected at the output to the differential stage. Both buffers comprise a resistor flown by a current which varies only as a function of the respective input voltage and of its resistance and therefore depends thermally exclusively on this resistance, and provide output voltages which depend upon these currents, so that the output current generated by the differential stage is temperature-independent.

Abstract: A temperature compensation circuit (FIG. 5a) has a controlled temperature compensated voltage drop across R1. A Schottky diode D1 is connected to the base of Q1 through resistor R1. The temperature coefficients of the base-emitter junction of Q1 and the diode D1 have a predetermined differential, preferably none. The forward voltage drop across D1 and the base-emitter junction are different, thereby establishing a controlled current through resistor R1 that is independent of temperature.

Abstract: A circuit dedicated to the stabilization of integrated circuit temperature charactristics is achieved by integrating on the same semiconductor material chip as the integrated circuit and a device comprised of a sensor having at least two resistors (R1, R2 and/or R3, R4) supplied between two voltages (DC1, DC2) used alone or in conjunction with differential circuit structure (T2, T3) supplied by a current source (T1), comprising a transistorized variable load impedance (T4, T5, T6, T7). The resistors have different temperature coefficients, and the output voltage (VA or VB) of the bridge is temperature dependent. The integrated must incorporate a voltage-controlled element (transistor or diode).

Abstract: A bipolar/CMOS regulator circuit for generating a CMOS gate-controlling voltage, which varies favorably with temperature, power supply voltage and process corner so as to yield a well-controlled CMOS current includes a bipolar bandgap regulator circuit portion (12) and a conversion circuit portion (14). The conversion circuit portion (14) is formed of a current mirror section (18), a current source section (20) and an output section (22).

Abstract: A temperature and processing compensated time delay circuit of the type which can be fabricated in a monolithic integrated circuit utilizes a field effect transistor (FET) (12) connected to the terminals of a charged capacitor (14). A bias voltage connected to the gate of the FET (12) varies with temperature in a manner to compensate for the changes in current which flows from the capacitor (14) through the FET (12) due to changes in temperature. The bias voltage also varies from one integrated circuit to another in a manner to compensate for variations in FET threshold voltage caused by variations in the processing of the integrated circuits.

Abstract: A voltage reference circuit (26) provides a stable output reference voltage over a wide temperature range. A high temperature curvature correction circuit (36) is enabled at a first predetermined temperature to adjust the output voltage accordingly. A low temperature curvature correction circuit (38) is enabled at temperatures below a second predetermined temperature to similarly affect a output voltage. The preferred embodiment, the high and low curvature correction circuits (36, 38) are operable to vary the current through one or more resistors in a bandgap circuit (26) or other reference circuit.

Abstract: An apparatus for controlling the intensity and on/off status of an incandescent light bulb as a function of the proximity of an object to a sensing plate. The frequency of a signal is varied from a nominal value when the presence of the object is sensed. A pulse is generated having a duration proportional to the time over which the signal if varied from its nominal frequency. The duration of the generated pulse, in relation to a pulse of predetermined width, is used to control a gated oscillator. The output of the gated oscillator is counted. The count obtained is used to control the operation of a TRIAC, which in turn connects power to the incandescent bulb.

Abstract: In a circuit for providing a bandgap voltage reference, a first current proportional to the thermal voltage V.sub.T is generated by a first current source. By means of current mirror operation, the first current induces a second current source to generate a proportional second current. The second current source is coupled to means which generates a first voltage which is proportional to the base-emitter junction of a bipolar transistor. The second current generates a second voltage which is then added to the first voltage to give the voltage reference.

Abstract: A localized cooling apparatus is provided for individually cooling integrated circuit chips mounted on a circuit board for insertion into a computer backplane. The cooling apparatus consists of a circuit board occupying a first slot and having an integrated circuit chip mounted thereon, the performance of which is known to improve by cooling, a heat removal assembly consisting of a heat sink attached to a card edge portion and occupying an adjacent second slot, and a thermoelectric cooler intimately bonded to both the chip and heat removal assembly. A controller provides power via the connector of the second slot to the thermoelectric cooler and stabilizes the temperature of the chip to a predetermined value.

Abstract: A circuit breaker with over-temperature protector and low error I.sup.2 t calculator is provided. The over-temperature protector includes a fixed current source which provides current to a resistive element to produce a voltage which thereacross which increases with a positive temperature coefficient as the surrounding temperature increases. The resistor is connected to the base-to-emitter circuit of a transistor. The base-to-emitter circuit has a minimum firing voltage which decreases with an increase in ambient temperature. The value of the resistive element, the amount of current provided by the fixed current source and the transistor base-to-emitter minimum firing voltage are chosen to cause a circuit breaker to be actuated. There is also provided an active memory device which is utilized to discharge a capacitor with a time constant which approximates the heat dissipating time constant associated with a conductor to be protected by the circuit breaker in question.

Abstract: An IC band-gap voltage reference including a pair of transistors having different emitter areas and driven by an amplifier feedback circuit to produce equal collector currents so as to develop an output voltage corresponding to the band-gap voltage. The amplifier output network includes a resistor network arranged to produce an output voltage which is a predetermined multiple of the band-gap voltage. The circuit provides for independent trimming of elements for adjusting the output voltage magnitude and its temperature coefficient.

Abstract: A non-saturating voltage output driver circuit. A controlling mechanism is connected to a current source, a reference voltage and a load. A pre-driver is also connected to the current source. Connected to the controlling mechanism, the pre-driver and the load is a down-level output driver, the output of which is dependent on the reference voltage, but kept out of saturation and substantially constant over a temperature range.

Abstract: A temperature constant Gm current reference circuit which is also independent of voltage across the circuit which includes a circuit for applying a substantially identical voltage to a semiconductor diode as well as to a branch circuit comprising a polysilicon resistor of predetermined doping level in series with plural unidirectional current carrying devices connected in parallel, preferably in the form of a multi-electrode transistor. From eight to twelve such unidirectional current carrying devices are required in the preferred embodiment.

Abstract: A voltage drop generator having a current source having reduced sensitivity to transistor base-emitter voltage process and temperature induced variations, is used to generate a precise voltage drop across a resistor. Transistor emitter area ratios are selected and an additional resistance is used in conjunction with the selected ratios to reduce the sensitivity (of the output voltage drop) to base-emitter voltages, to provide substantial improvement in process and temperature dependent output variations.

Abstract: A monolithic integrated circuit generates a programmable time delay under control of a digital work. The delay is generated by comparing a ramp signal to a threshold determined by the value of the digital word and appears as a time difference between a trigger pulse and a pulse generated when the value of the ramp voltage equals the value of the threshold voltage. The ramp voltage is generated by a simple resistance/capacitance charging circuit whose time constant can be adjusted by the user. The threshold voltage is set by a digital-to-analog converter (DAC) and resistor circuit which converts the digital control word into a variable voltage. In order to stabilize the device against changes in temperature and power supply variations, a voltage coupling circuit forces the threshold voltage to track changes in the ramp voltage caused by temperature and power supply variations.

Abstract: An output transistor (T.sub.1) is to be protected from damage due to excessive currents. This transistor supplies a current (I.sub.o) to a load (3) and is driven by a driver transistor (T.sub.2). The base-emitter junction of a current-sensing trnsistor (T.sub.3) is connected in parallel with that of the output transistor (T.sub.1). The collector current of transistor (T.sub.3) is a measure of the current (I.sub.o) of the output transistor (T.sub.1). A current generator (5) supplying a reference current (I.sub.ref) is coupled to the collector of the current-sensing transistor (T.sub.3). If the collector current of the current-sensing transistor exceeds the reference current (I.sub.ref) the protection circuit is activated so that the driver transistor is bottomed via an emitter-follower (T.sub.4). The base current of transistor T.sub.1 is thereby limited. Thus, the output current of the output transistor is limited to a maximum value which is substantially equal to the product of the reference current (I.sub.

Abstract: A three-phase current output circuit for driving a three-phase brushless motor, the output circuit having a first current source and a second current source with positive temperature coefficients which are provided so as to negate a negative temperature coefficient which causes undesirable reduction of motor torque.

Abstract: A power supply control system controls at least two variable power supplies feeding a common load connected to a common output terminal. A sensor monitors the current drawn by each power supply in dependence upon the difference detected in a sense to reduce the difference to zero. A summing circuit sums the outputs of all the comparators. Another comparator compares the output of the summing circuit with a zero level and produces an output to modify the reference signal. The loops comprising each comparator and the further comparator each act in a sense to reduce the output of the summing circuit to zero and in this way the system tends to maintain a balanced output from all supplies so that each supply shares the power requirement of the load according to its capacity while at the same time maintaining the output voltage at a level corresponding to the average of the nominal voltages of the individual supplies.

Abstract: Programmable monolithic integrated circuit current mirrors configured as either current sources or current sinks include mixed MOS and bipolar technology on a substrate, wherein the master and slave elements each include a silicon-based emitter resistor having a positive temperature coefficient matched to the negative temperature coefficient of the V.sub.be of an associated bipolar transistor, for making the ratios of the master element current to the individual slave element currents substantially insensitive to dynamic temperature gradients produced in the associated substrate. Each slave is independently and individually compensated.

Abstract: Apparatus for monitoring the temperature of a circuit component in a circuit arrangement wherein the circuit can be influenced via a temperature sensor when a predetermined value is exceeded for the purpose of preventing undesired high temperatures. This apparatus is improved for its use in inherently safe electronic switching circuits in that it provides the smallest possible volumetric configuration and, in addition, enables a reliable switching characteristic to be realized which is selectable within narrow temperature ranges. It is intended that the testing of its functional capability should be possible with the aid of simple means when in the built-in condition. For this purpose, a plurality of circuit components are connected in series or in parallel.

Abstract: An improved CMOS bandgap voltage reference in which a magnified current derived from a thermal voltage reference produces a voltage drop across a resistor. The resistor in turn couples to a single bipolar transistor which is part of the thermal voltage reference. The bandgap voltage is the sum of the voltage across the resistor and the voltage across the bipolar transistor. In addition, the immunity of a bandgap voltage reference to variations in power supply variations is improved by having a differential amplifier sense the voltages at the control current input and the output of a current mirror in the thermal voltage reference portion of the bandgap voltage reference and adjusting the power supply voltage to the thermal voltage reference until the sensed voltages are substantially the same.

Abstract: A battery charger supplies to a battery an output voltage having a desired temperature coefficient of voltage. The charger includes an operational amplifier having a summing junction to which a reference current and a feedback signal derived from the amplifier output are supplied. The V.sub.be multiplier circuit includes a bipolar transistor which is biased into its active region so that the charging voltage supplied by the amplifier is temperature corrected in accordance with a negative coefficient of voltage characteristic of the transistor.

Abstract: A temperature and processing compensated time delay circuit of the type which can be fabricated in a monolithic integrated circuit utilizes a field effect transistor (FET) (12) connected to the terminals of a charged capacitor (14). A bias voltage connected to the gate of the FET (12) varies with temperature in a manner to compensate for the changes in current which flows from the capacitor (14) through the FET (12) due to changes in temperature. The bias voltage also varies from one integrated circuit to another in a manner to compensate for variations in FET threshold voltage caused by variations in the processing of the integrated circuits.

Abstract: A non-linear temperature correction circuit is provided which utilizes, in one embodiment, a pair of semiconductor elements such as a pair of transistors electrically connected to a common biasing current having a negative temperature coefficient and a negative temperature coefficient voltage is applied between the bases of the transistors. The output of one of the transistors is a non-linear output current which is non-linear with respect to temperature and where the output current has an inflection point.

Abstract: Various voltage and current sources which are substantially independent of the positive supply rail are provided, some of which are also temperature independent.

Abstract: A following voltage/current regulator includes a field effect transistor (FET) (48) connected in series between an unregulated voltage source (44) and a load, such as a motor bridge circuit (50). The conduction of the FET is controlled by a control circuit (56) which measures the input voltage to the FET source, the output voltage from the FET drain and the current drawn by the load. Initially, when power is turned on, the inrush current to the load is limited until a predetermined voltage differential between the input and output voltages is achieved at steady state. Then, the voltage regulator maintains the predetermined voltage differential to provide a well regulated output voltage to the load despite fluctuations in supply voltage. This "following" action limits the heat disipation and protects the FET. Because the voltage regulator uses no inductors or transformers, there are no saturation problems and the circuit may be compactly packaged.

Abstract: A computer element performance enhancer having peltier device providing cooling to the critical computer elements of a desk top computer. A peltier device controller regulates the flow of power to the peltier device such that the computer elements are maintained in a below ambient temperature range. An adjustable power supply is connected to and supplies power to the critical computer elements. A power supply controller regulates the adjustable power supply such that a local voltage at the computer elements is maintained at a precision high voltage range. A dual speed clock generator is connected to the computer elements and runs the computer elements at a higher rate of speed when the computer elements are within the prescribed temperature and voltage ranges.

Abstract: A current source circuit comprises a first enhancement mode field effect transistor arranged as a current source. A drive voltage which is generated by a second depletion mode field effect transistor and a third depletion mode field effect transistor is applied to the drive electrode of this first transistor. The drive voltage is such that the output current of the first transistor is substantially independent of temperature variations.

Abstract: A bipolar bandgap reference circuit employing three resistors of selected nominal resistance values and a method of trimming the values of two of the resistors to cancel the slope and curvature of output voltage due to thermal drift. One of the resistors provides a positive temperature coefficient to counter the temperature dependency of bipolar base-emitter characteristics; this resistor is not trimmed. The other two resistors are thin-film, low TC devices and are "trimmed" (i.e., adjusted) sequentially, to match calculated values intended to minimize the first and second derivatives of the bandgap cell output, as a function of temperature.

Abstract: A device for regulating delivery of power from an AC voltage source to a load such as a lamp, a motor, a heating element or the like is described. Electronic circuitry responsive to the AC voltage generates a periodic signal whose magnitude indicates the instantaneous phase angle of the AC voltage relative to the most recent zero crossover of the AC voltage throughout the entirety of each half cycle of operation. A comparator generates a triggering signal when the phase angle signal corresponds to a threshold signal which may be manually set by adjustment of a voltage divider or which may be generated by a sensor in response to a predetermined condition, such as ambient light level or temperature, which is to be regulated by appropriate delivery of power to the load. The triggering signal is applied to a triac series connected with the load to initiate conduction of load current.

Abstract: A bandgap reference circuit is described in which two transistors share a current with their bases coupled together and to an output terminal. A pair of resistors is coupled in series between the emitter of one of the transistors and ground, the emitter of the other transistor being coupled to a node between the resistors. A further transistor is coupled between the output terminal and the node with its base coupled to a second node between two further resistors connected in series between the output terminal and ground. The further transistor and resistors allow the circuit to be compensated for higher order temperature dependence.

Abstract: A band-gap voltage reference having reduced output voltage noise. The invention embraces several novel concepts, including the optimization of transistor area ratios as used in the band-gap device, the selection of multiple transistors in the Vbe, the section of the current range for the band-gap device, resistive loads to provide minimum load noise and selective signal filtering before the output amplifier. The resulting device according to the present invention exhibits lower output voltage noise than previous band-gap voltage references, without sacrificing other important voltage reference parameters, such as line regulation, load regulation, temperature coefficient, and stability.

Abstract: A temperature compensated bandgap voltage reference circuit employs an npn transistor based bypass circuit to maintain a constant collector current within the reference circuit. This bypass circuit draws a nominal current from the bandgap voltage reference circuit. The value of this current is set by a bias circuit responsive to changes in the supply voltage. As the supply voltage changes, the bias circuit varies the conductance of a bypass transistor to draw more or less current and thereby maintain the collector current within the reference circuit constant.

Abstract: A two-terminal temperature-compensated current source includes a first transistor having its emitter connected to a first terminal, its base connected to the base of a second transistor, and its collector coupled to a current mirror. The second transistor has its emitter coupled to the first terminal by a first resistor and its collector coupled to the current mirror. A second resistor is coupled between the first terminal and the base of the first transistor. The current mirror is coupled between a second terminal and the collectors of the first and second transistors so that all current supplied to the current mirror from the second terminal flows into the collectors of the first and second transistors. A third transistor has its base coupled to the collector of the first transistor, its emitter coupled to the base of the first transistor, and its collector coupled to the second terminal.

Abstract: A voltage reference circuit including a Brokaw Cell band-gap reference circuit is provided with breakpoint compensation to adjust the temperature coefficient of the reference voltage provided by the Brokaw Cell as a function of temperature. The voltage reference circuit also includes a thermal limit transistor which is biased by a voltage having a positive temperature coefficient. The thermal limit transistor draws a rapidly increasing current when the operating temperature reaches a predetermined value.

Abstract: A current source provides an output current whose magnitude is substantially independent of changes in temperature. In each of three embodiments (50, 100, 120), one or more bipolar transistors are employed to provide a compensating current which is dependent on the base-to-emitter voltages, V.sub.BE, of such bipolar transistors. The compensating current changes with temperature so as to offset changes in the uncompensated output current so that the total output current is substantially independent of V.sub.BE. The three embodiments employ current mirror circuits (10, 122) that provide a current source of simple circuit design that is operable with the use of a single power supply at a relatively low voltage.