Abstract: A sense amplifier circuit, memory device and related operation methods are provided. The sense amplifier circuit includes an amplification circuit for amplifying a voltage signal and a compensation circuit coupled to the amplification circuit. The amplification circuit includes a first inverting amplifier and a second inverting amplifier cross-coupled with each other, with the first inverting amplifier connected to a first bitline and the second inverting amplifier connected to a second bitline. The compensation circuit includes a first, a second, a third, and a fourth switch circuits, and is configured to generate a compensation voltage between the first bitline and the second bitline by conducting charge injections through operating the switch circuits to compensate an input-referred offset voltage of the amplification circuit.

Abstract: The present application provides a driving circuit of power devices, a switching circuit and a power conversion circuit. The driving circuit is configured to control switching actions of N power devices connected in parallel, where N?2 and N is a positive integer; the driving circuit includes a driving input circuit and a common magnetic bead, where a first end of the driving input circuit is electrically connected to N first ends of the common magnetic bead, N second ends of the common magnetic bead are electrically connected to control ends of the N power devices in a one-to-one correspondence, and a second end of the driving input circuit is electrically connected to second ends of the N power devices.

Abstract: A circuit includes a first switch assembly having a first input node and a first output node, and a second switch assembly having a second input node and a second output node. The circuit further includes a third switch assembly an operational amplifier, and a buffer. The third switch assembly has a third input node and a third output node. The third input node is coupled to the second output node, and the third output node is coupled to the first output node. The buffer has a buffer input and a buffer output. The buffer input is coupled to an input stage of the operational amplifier. The buffer output is coupled to the third switch assembly.

Abstract: In a semiconductor switch, a resistance value between a current input terminal to which a current is input and a current output terminal from which a current is output decreases as a voltage of a control terminal based on a potential of the current output terminal increases. A booster circuit is disposed on a path extending from the current input terminal to the control terminal. The booster circuit boosts a voltage input from the current input terminal side and applies the boosted voltage to the control terminal. A switch is connected between the control terminal and the current output terminal of the semiconductor switch. The switch is switched off by power consumption. The power consumption stops and the switch switches on if the supply of power to the booster circuit stops.

Abstract: A circuit, intended to be associated in series with a load to be powered including a first field-effect transistor; at least one second field-effect transistor, associated in parallel with the first transistor; and at least one sensor of information representative of a current transmitted to said load, the gate of the second transistor being coupled to an output of the sensor.

Abstract: A device includes a semiconductor die including a transistor. The transistor includes a plurality of parallel transistor elements. Each transistor element includes a drain region, a source region, and a gate region. The semiconductor die includes a first temperature sensor between a first transistor element in the plurality of transistor elements and a second transistor element in the plurality of transistor elements. The first temperature sensor is configured to generate a first output signal having a magnitude that is proportional to a temperature of the first temperature sensor.

Abstract: A voltage balance circuit including first and second semiconductor devices connected in series with each other is provided with a first transformer having a primary winding and a secondary winding, a second transformer having a primary winding and a secondary winding. A pair of capacitors connected in series with each other and connected between the output terminals of the plurality of semiconductor devices. A first control signal is applied to the control electrode of the first semiconductor device via the primary winding of the first transformer. A second control signal is applied to the control electrode of the second semiconductor device via the primary winding of the second transformer, with one end of each secondary winding connected to each other.

Abstract: A power circuit with a first transistor, including a first terminal connected to a first node, a second terminal connected to an input node, and a control terminal connected to a first control node, and a second transistor, including a first terminal connected to the first node, a second terminal connected to an output node, and a control terminal connected to a second control node. A third transistor includes a first terminal connected to the first control node, a second terminal connected to a second node, and a control terminal, and a fourth transistor includes a first terminal connected to the output node, a second terminal connected to the second control node, and a control terminal connected to a third node. The power circuit also includes a current limiting circuit coupled between the second node and the third node.

Abstract: A device for driving a control terminal of a transistor includes an input terminal, a transformer including an input winding and an output winding, the input winding being coupled to the input terminal, an n-stage buffer circuit configured to generate a drive signal for the control terminal of the transistor, the n-stage buffer circuit being coupled to a first end of the output winding, and a positive feedback path coupled to an output of a stage of the n-stage buffer circuit to provide a DC offset to an input of the n-stage buffer circuit.

Abstract: A transconductance circuit has an input terminal (VIN) and an output terminal (Out), a first current source (4) having a gate connected to said input terminal (VIN); and a second current source (5), in parallel with said first current source, and having a higher transconductance and a wider dynamic range than the first current source. The current sources are configured so that at a low input voltage only the first current source (4) is on. A voltage drop circuit provides a lower bias voltage for the second current source than for the first current source.

Abstract: A novel nonlinear impulse sampler is presented that provides a clock sharpening circuit, sampling stage, and post-sampling block. The clock sharpening circuit sharpens the incoming clock while acting as a buffer, and the sharpened clock is fed to the input of the sampling stage. The impulse sampling stage has two main transistors, where one transistor generates the impulse and the other transistor samples the input signal. Post-sampling block processes the sampled signal and acts as a sample and hold circuit. The architecture uses an ultrafast transmission-line based inductive peaking technique to turn on a high-speed sampling bipolar transistor for a few picoseconds. It is shown that the sampler can detect impulses as short as 100 psec or less.

Abstract: The invention relates to an apparatus and methods for operation in relatively high radiation fields to remotely switch signal devices through a shared single main umbilical signal cable. The invention is particularly suitable for use in a nuclear reactor, such as a boiling water reactor, and in difficult to access areas in the reactor pressure vessel. One or more main umbilical cables connect a control station to an enclosure housing a signal switching device. The signal switching device allows several signal generating/receiving devices, such as cameras and ultrasonic probes, to be controlled by the one or more main umbilical cables.

Abstract: A sequence circuit includes first through third signal terminals, first through ninth resistors, and first through fifth electronic switches. The sequence circuit receives a first signal through the first signal terminal. The sequence circuit receives a second signal through the second signal terminal. The sequence circuit outputs a third signal through the third signal terminal. The sequence circuit is used to ensure the sequence of the first through third signals.

Abstract: The present disclosure provides a power semiconductor switch series circuit. The power semiconductor switch series circuit includes a plurality of series modules and a system control module. Each series module has a power semiconductor switch; a drive module for driving each power semiconductor switch to be turned on or turned off; a short-circuit detection unit for outputting at least one detection signal; an equalizer circuit; a comparison module for comparing the detection signal with a predetermined threshold, and outputting a short-circuit signal when the detection signal exceeds the predetermined threshold; and a soft turn-off module for receiving the short-circuit signal and outputting a second control signal. The system control module receives the short-circuit signal and outputs a first control signal.

Abstract: An electronic apparatus is provided which includes switching elements, resonance suppression resistors which have first ends connected to control terminals of the switching elements and second ends having a common connection, an on-drive circuit which has an on-drive resistor and is connected to a drive power circuit, and which is supplied with voltage from the drive power circuit and applies electric charge to the control terminals of the switching elements via the on-drive resistor to turn on the switching elements, and an off-drive circuit which has an off-drive resistor and releases electric charge from the control terminals of the switching elements via the off-drive resistor to turn off the switching elements. A resistance of the off-drive resistor is set to be smaller than a resistance of the resonance suppression resistors. The off-drive circuit releases electric charge from the control terminals of the switching elements not via the resonance suppression resistors.

Abstract: A switch is capable of performing switching, while reducing distortion with respect to amplitude of a high frequency signal. The switch includes: an input terminal to which a high frequency signal is input; a first switching unit connected between the input terminal and a first output terminal and selectively outputting the high frequency signal through the first output terminal; and a second switching unit connected between the input terminal and a second output terminal and selectively outputting the high frequency signal through the second output terminal. Each switching unit includes an impedance transformer installed on a signal line, a bipolar transistor having an emitter grounded, a collector connected to the signal line, and a base receiving current according to a control voltage applied thereto; and a bipolar transistor having a collector grounded, an emitter connected to the signal line, and a base receiving current according to the control voltage.

Abstract: A switch circuit and an electronic device using the same include a power switch transistor, a controlling circuit, a regulated capacitor, and a capacitor. The power switch transistor is connected between an input and an output of the switch circuit. An output of the controlling circuit is connected to a controlling electrode of the power switch transistor and outputs pulse width modulation (PWM) signals to turn the power switch transistor on and off. The regulated capacitor is connected between an output of the switch circuit and ground. The capacitor is connected between an output of the controlling circuit and ground for increasing an inclination of a rising edge and a falling edge of PWM signals to slow down the speed of switching the power switch transistor on and off, thereby making the regulated capacitor charge slowly and the output voltage of the switch circuit stable.

Abstract: A switch is capable of performing switching, while reducing distortion with respect to amplitude of a high frequency signal. The switch includes: an input terminal to which a high frequency signal is input; a first switching unit connected between the input terminal and a first output terminal and selectively outputting the high frequency signal through the first output terminal; and a second switching unit connected between the input terminal and a second output terminal and selectively outputting the high frequency signal through the second output terminal. Each switching unit includes an impedance transformer installed on a signal line, a bipolar transistor having an emitter grounded, a collector connected to the signal line, and a base receiving current according to a control voltage applied thereto; and a bipolar transistor having a collector grounded, an emitter connected to the signal line, and a base receiving current according to the control voltage.

Abstract: The present disclosure provides a power semiconductor switch series circuit. The power semiconductor switch series circuit includes a plurality of series modules and a system control module. Each series module has a power semiconductor switch; a drive module for driving each power semiconductor switch to be turned on or turned off; a short-circuit detection unit for outputting at least one detection signal; an equalizer circuit; a comparison module for comparing the detection signal with a predetermined threshold, and outputting a short-circuit signal when the detection signal exceeds the predetermined threshold; and a soft turn-off module for receiving the short-circuit signal and outputting a second control signal. The system control module receives the short-circuit signal and outputs a first control signal.

Abstract: Techniques are disclosed for reducing off-state leakage current in a differential switching device. The techniques can be embodied, for example, in a method that includes receiving a differential input signal at a differential input of each of a primary switch and a dummy switch. In an enabled-state of the device, the method further includes passing the differential input signal to a differential output of the primary switch. In a disabled-state of the device, the method further includes canceling off-state leakage current at the differential output of the primary switch, by virtue of the dummy switch having its differential output reverse-coupled to the differential output of the primary switch. The method may further include preventing the dummy switch from passing signals other than off-state leakage signals. The techniques can be embodied, for instance, in a switching device.

Abstract: Described is a modular switch for an electrical converter. The modular switch is provided with a first series circuit including a first controllable power semiconductor component and a first diode as well as with a second series circuit including a second diode and a second controllable power semiconductor. The connecting point between the first power semiconductor component and the first diode forms a first terminal and the connecting point between the second diode and the second power semiconductor component forms a second terminal of the modular switch. Also provided is a capacitor, wherein the first series circuit and the second series circuit and the capacitor are switched parallel to each other.

Abstract: A switch device executes a multi-state function to a computer. The computer has a system on chip. The switch device comprises a switch, a power output circuit, a control circuit, a timer circuit and an interface circuit of the system on chip. A user can press the switch, the control circuit controls the power output circuit to output a control signal to the system on chip for controlling the computer turning on or going into suspend state. When the user continues to press the switch, the timing circuit will execute a timer function to the switch device.

Abstract: A semiconductor device has pluralities of grid array terminals forming a grid array structure, e.g. a BGA structure, in which the output end of a built-in switch circuit is connected to multiple terminals of the grid array structure, thereby reducing the current that flows through each of the multiple terminals below a permissible level and minimizing the heat due to contact resistances of the multiple terminals in contact with the IC socket of the semiconductor device. Each pair of nearest neighbors of the multiple terminals is interposed by at least one further array terminal. The multiple terminals are all located at the outermost peripheral terminal positions of the grid array structure. Thus, the heat generated in the respective multiple terminals connected to the switch circuit is reduced, thereby minimizing the possibility of hazardous melting of the terminals.

Abstract: The present techniques include methods and systems for operating converter to maintain a lifespan of the converter. In some embodiments, the operating frequency of the converter may be increased such that stress may be reduced on the bond wires of the converter. More specifically, embodiments involve calculating the aging parameters for certain operating conditions of the converter operating in a maximum power point tracking (MPPT) mode and determining whether the MPPT operation results in aging the converter to a point which reduces the converter lifespan below a desired lifespan. If the MPPT operation reduces the converter lifespan below the desired lifespan, the frequency of the converter may be increased such that the converter may be controlled to operate at a percentage of MPPT. Thus, in some embodiments, power output may be optimized with respect to maintaining a desired lifespan of the converter.

Abstract: The electronic apparatus includes a direct-current voltage generation part that generates a direct-current voltage from a commercial power supply; a switching part that switches between an on-state in which the direct-current voltage from the direct-current voltage generation part is output, and an off-state in which the output of the direct-current voltage is shut down, a control part that controls operation of the direct-current voltage generation part; and a power supply maintaining part connected to the direct-current voltage generation part, the power supply maintaining part instructing the switching part to be in the on-state or the off-state, and consequently, enables provision of a soft-switch electronic apparatus that after recovery of a power failure, automatically returns to a state before occurrence of the power failure.

Abstract: A power semiconductor module includes semiconductor elements of a first system constituting each of arms in a circuit of the first system, semiconductor elements of a second system constituting each of arms in a circuit of the second system, a plurality of DC electrode conductors including a common DC electrode conductor joined to the semiconductor elements of the first and second systems, and a plurality of AC electrode conductors joined to the respective semiconductor elements of the first and second systems. Each of the semiconductor elements of the first and second systems is interposed between the DC electrode conductor and AC electrode conductor.

Abstract: The present invention relates to an electronic equipment mode switching apparatus and method based on a skin contact made by a user using the electronic equipment, thereby being capable of minimizing the power consumption of electronic equipment and also of instantly operating electronic equipment as soon as skin contact is made. The electronic equipment mode switching apparatus includes skin contact detection means for detecting electricity generated when a user's skin is touched, logic circuit means for generating a mode switching signal to switch a power supply mode of an electronic device when skin contact is detected by the skin contact detection means, and mode switching means for switching the power supply mode of the electronic device in response to the mode switching signal generated by the logic circuit means.

Abstract: Provided is an SPDT switch having improved isolation characteristics in an RF band. The SPDT switch includes a serial switching unit, a current sink unit, a switching isolation unit, and a DC blocking unit. The serial switching unit includes first and second HBTs. The current sink unit sinks a current flowing from a common input terminal to each of first and second output terminals of the serial switching unit. The switching isolation unit causes an unselected output terminal of the first and second output terminals to be electrically isolated from the common input terminal when the serial switching unit operates. The DC blocking unit blocks a DC between the first HBT and the first output terminal and a DC between the second HBT and the second output terminal. Accordingly, it is possible to provide better insertion-loss and isolation characteristics in higher frequency bands than typical switches.

Abstract: The invention relates to a tap switch for uninterrupted changeover between two winding taps (tap n, tap n+1) of a tapped transformer, wherein each of the two winding taps is connected to the common outgoing load line via in each case a mechanical switch (Ds) and a series circuit which is arranged in series therewith and which is composed of two oppositely connected IGBTs (Ip, In). According to the invention, each IGBT is bridged by in each case a specially dimensioned varistor (Vp, Vn) connected in parallel therewith.

Abstract: A load driving circuit and a multi-load feedback circuit is disclosed. The load driving circuit and the multi-load feedback circuit are adapted to drive a LED module that has a current balancing circuit for balancing the currents flowing through LEDs. The load driving circuit and the multi-load feedback circuit modules the electric power transmitted by the LED driving apparatus to a LED module according to voltage level(s) of current balancing terminals having insufficient voltage in the current balancing circuit, and so the voltage levels of the current balancing terminals are higher than or equal to a preset voltage level, further increasing the efficiency thereof.

Abstract: A switching circuit includes a first switching module, a second switching module, a first relay module, a second relay module, and a processing module. The first switching module includes a switch and a first transistor. The base of the first transistor functions as a first reset terminal. The second switching module includes a second transistor. An output terminal of the second relay module functions as a second reset terminal. Two input terminals of the processing module are connected to the first and second reset terminals respectively. The processing module resets a system with a first type or a second type according to voltages of the first and second reset terminals.

Abstract: A current-source converter includes high-arm side switching elements and low-arm side switching elements. A voltage between the DC power supply lines is detected as a line voltage of an input line, based on a conduction pattern of the high-arm side switching elements and the low-arm side switching elements.

Abstract: Semiconductor devices and methods are disclosed wherein a switching element or a current path is coupled to a substrate, and wherein a further element is coupled to said substrate and a control input of said switching element or said current path. Accordingly, in at least one embodiment, a semiconductor device comprises a substrate and a switching element with a control input coupled to the substrate. The semiconductor device includes a compensation element having a control input and an output. The control input of the compensation element is coupled to the substrate and the output of the compensation element is coupled to the control input of the switching element.

Abstract: A method and an arrangement are disclosed for balancing load between parallel connected inverter modules, which inverter modules are arranged to supply a common load. The method can include providing similar switching instructions for parallel connected inverter modules, determining on the basis of phase currents of each parallel inverter module a first time period for each output phase of each inverter module for correcting current imbalance by advancing or delaying turn-on or turn-off time instants of switch components of the inverter modules, and advancing or delaying the turn-on or turn-off time instants of the switching instructions based on the first time period.

Abstract: Disclosed is a control circuit for controlling a controllable power semiconductor switch, and to a power semiconductor module. The control circuit comprises at least two circuit sets, each having a power driver. The power driver of each of the circuit sets is provided with power via impedance components having an impedance other than zero.

Abstract: A semiconductor power switch comprises at least a first IGBT and a second IGBT. The collectors of the first and second IGBTs are connected to each other, and the emitters of the first and second IGBTs are connected to each other. The first IGBT is an IGBT type with a comparatively low collector-emitter on-voltage and a comparatively high turn-on or turn-off switching energy. In contrast thereto, the second IGBT is an IGBT type with a comparatively high collector-emitter on-voltage and a comparatively low turn-on or turn-off switching energy. Both IGBTs receive gate signals from a control circuit for switching the power switch on during a first time interval and switching the power switch off during a second time interval. The control circuit is designed to supply an on-signal to the second IGBT during the whole first time interval and another on-signal to the first IGBT during only a part of the first time interval, which is less than the whole.

Abstract: A circuit arrangement for driving an electronic component with the output signal (V6) from a microprocessor (MP), includes: the electronic component with a control input; a microprocessor (MP), which provides an output signal (V6) at an output (A1); wherein it furthermore includes: a first bipolar transistor (Q5) in common-base connection, whose emitter is coupled to the output (A1) of the microprocessor (MP); a second bipolar transistor (Q7) in common-emitter connection, whose base is coupled to the collector of the first bipolar transistor (Q5), wherein the collector of the second bipolar transistor (Q7) is coupled to the control input of the electronic component. Moreover, it relates to a corresponding method for driving an electronic component with the output signal (V6) from a microprocessor (MP).

Abstract: A first semiconductor element having a junction electrode to be connected to a first node of a bidirectional switch circuit is mounted on a first metal base plate to be a heat dissipation plate, and a second semiconductor element having a junction electrode to be connected to a second node of the bidirectional switch circuit is mounted on a second metal base plate to be a heat dissipation plate. The junction electrode of the first semiconductor element has the same potential as that of the first metal base plate, and the junction electrode of the second semiconductor element has the same potential as that of the second metal base plate. Also, the respective metal base plates and non-junction electrodes of the respective semiconductor elements are connected by metal thin wires, respectively, thereby configuring the bidirectional switch circuit.

Abstract: A power supply switching circuit includes an input terminal (2) for receiving a signal from a motherboard, an output terminal (4) to output a control signal, a first Bipolar Junction Transistor (BJT) (5), and a second BJT (7). A base of the first BJT is connected to the input terminal via a base bleeder circuit. A collector of the first BJT is connected to a stand-by power supply terminal (10) via a collector resistor. A base of the second BJT is connected to the collector of the first BJT. A collector of the second BJT is connected to a system power supply terminal (12) via a collector resistor. The collector of the second BJT is connected to the output terminal. Emitters of the first and second BJTs are grounded.

Abstract: A polarity insensitive solid state switch controlling a shunt load, wherein the switch includes first and second transistors connected in anti-parallel in series with the shunt load; and a longitudinal current sensor controlling the control electrodes of both transistors. The current sensor may be a current sensing resistor in series with a second load. Each transistor may be a bipolar transistor and the current sensing resistor may be connected between the base and emitter of each transistor.

Abstract: The invention concerns a switching circuit (20) adapted to generate a pulse when there occurs a rising edge of a signal applied on an input terminal (CTRL), comprising: a first NPN type bipolar transistor (TN2) whereof the transmitter is connected to the input terminal; a second transistor (TP2) whereof a control electrode is connected, through a first resistor (Re2), to the input terminal, the base of the first transistor being connected to a supply potential (VDD) by the second transistor in series with a second resistor (Rp2); and a third transistor (TN3) connecting an output terminal (22) of the switching circuit to a reference potential (GND) and whereof a control electrode is connected to the collector of the first transistor (TN2).

Abstract: A voltage follower includes a follower stage including first and second bipolar junction transistors connected in cascade, and a first current generator connected to the follower stage for biasing the first and second bipolar junction transistors. A cascode stage is connected between the first current generator and the first bipolar junction transistor, and a second current generator is connected between the first bipolar junction transistor and a first voltage reference. The voltage follower dissipates less power when the output current is small.

Abstract: A semiconductor circuit for switching and/or amplitude influencing of an analog desired signal fed to the input (EA, AE) of the circuit (1) to an analog actual signal in the high-frequency range generated by the circuit at the output (AE, EA). The circuit (1) has two bipolar transistors (T1, T2) arranged with respect to one another such that the collector terminal (K1, K2) of the one bipolar transistor (T1, T2) is connected with the emitter terminal (E2, E1) of the other bipolar transistor (T2, T1) and vice-versa. The bipolar transistors (T1, T2) are controlled by a control quantity fed to the base terminals (B1, B2) of the transistors (T1, T2).

Abstract: A thermally stabilized cascode heterojunction bipolar transistor (TSC-HB) having the current and power generation regions in separate temperature zones, each transistor collector in a cold zone connected directly and individually to an emitter terminal of a corresponding transistor in a hot zone, thereby limiting the current available to the emitter of the transistor in the hot zone. Such an interconnection of transistors prevents the transistor in the hot zone from drawing more current from other transistor sources when increases in temperature occur. This achieves thermal stability and prevents the transistors from overheating and burning out.

Abstract: The present invention relates to an integrated circuit bidirectional switch formed from bipolar transistor devices, in which the saturation voltage is sought to be reduced. More specifically, an integrated NPN bipolar transistor is formed with oxide insulation, and the normal direction of current flow is from the emitter to collector, and an integrated PNP bipolar transistor is formed with oxide insulation, and the normal direction of current flow is from the collector to emitter.

Abstract: A switching element having two signal inputs and two signal outputs, in which switching element a first and second transistor are provided, the base terminals of which are connected to one another and are connected to a drive unit. The collector terminals of the first and second transistor form the two signal outputs and the emitter terminals of the first and second transistor form the two signal inputs to which a current source can be connected in each case. The switching element provides for implementation of a switching system with low power loss.

Abstract: An insulated gate bipolar transistor (IGBT) device is a semiconductor device comprising a main IGBT 1, a sub IGBT 20, and a current limiting circuit 30 on one chip. It has an n-channel main IGBT 1, sub IGBT 20, and sensor IGBT 2 connected in parallel, whose current is controlled by a gate signal IN, an emitter resistor RE of the sensor IGBT 2, and an n-channel MOSFET 7 to which a voltage drop of the emitter resistor RE is applied as a gate voltage for fast discharging gate capacities C1, C2, and C20 of the IGBT 1, IGBT 2, and IGBT 20. Threshold voltage VTHB of the sub IGBT 20 is set high on the order of 1 V as compared with threshold voltage VTHA of the main IGBT 1 and the sensor IGBT 2. When a load 6 is discharged, the gate capacities C1, C2, and C20 are discharged dominantly, thus only the sub IGBT 20 is cut off and the main IGBT 1 and the sensor IGBT 2 perform the current limit operation, so that the load short-circuiting current can be stepped down drastically.

Abstract: An integrated circuit fast transmission switching device is provided which comprises a first input/output lead having a bus capacitance Cb; a second input/output lead having a bus capacitance Cb; a first bidirectional field-effect transistor having an internal resistance Ri and an internal capacitance Ci including a first input/output terminal and a second input/output terminal and a gate terminal, said first terminal being connected to said first lead and said second terminal being connected to said second lead, so as to pass bidirectional external data signals between said first and second leads when said transistor is turned on and so as to block the passage of external data signals between said first and second leads when said transistor is turned off; wherein Ri and Ci for the field-effect transistor are such that Ri(Ci+Cb) is less than 6.

Abstract: An analog switch is constructed using two bipolar junction transistors. The emitter of the first transistor is coupled to the emitter of the second transistor, and preferably the base of the first transistor is coupled to the base of the second transistor. The collectors of the transistors form the terminals of the analog switch. A current source is coupled to the bases of both transistors. The current source produces a drive current sufficient to forward bias the base-emitter junctions of both transistors. In this forward biased state, the collector of the first transistor and the collector of the second transistor are electrically coupled. A bias voltage source is coupled via a switch to the bases of both transistors. The bias voltage source produces a voltage sufficient to reverse bias the base-collector junctions of both transistors. In this reverse biased state, the electrical connection between the collector of the first transistor and the collector of the second transistor is broken.

Abstract: A birectional transistor switch for large signal voltages comprises a first (T1) and a second (T2) transistor arranged in series, which are supplied with base current under command of a control signal in order to short-circuit a signal terminal (ST) to a reference terminal (RT) which is connected to the substrate of the circuit. When the transistor switch is open large negative voltage excursions of the signal (U) on the signal terminal (ST) will fire a thyristor formed by the first transistor (T1) and a parasitic transistor (TP) and thus cause an undesired short-circuit between the signal terminal and the reference terminal (RT). This is prevented in that under these conditions the node (N) between the two transistors is short-circuited to the reference terminal (RT), as a result of which the loop gain in the thyristor becomes so small that this thyristor is no longer fired.