摘要:
A transient driver circuit for use with a logic circuit having an emitter-follower output stage that sources current to a load connected to an output thereof in response to an applied logic signal being at a first logic level. The transient driver circuit includes a first NPN transistor the collector-emitter path of which is coupled between the output of the logic circuit and the negative power supply rail, a second NPN transistor having its collector-emitter path couple between a positive power supply rail and the collector of the first NPN transistor and its base adapted to receive the logic signal and feedback circuitry that is responsive to a rise in the collector voltage of the second NPN transistor occurring as the logic signal switches to a second logic level for supplying current drive to the base of the first NPN transistor thereby turning it on to sink a large transient current at the output of the logic circuit.
摘要:
A memory circuit is provided wherein the speed of the downward transition of the memory cell is increased. A plurality of memory cells are coupled between a select line and a current drain line. A first means is coupled to the select line for providing current to the plurality of memory cells and is responsive to a select signal having first and second states. A first PNP transistor has an emitter coupled to the current drain line for drawing any charge from the plurality of memory cells when the select signal transitions downward. A second means is coupled to the base of the first PNP transistor and is responsive to the select signal for setting the current level in said first PNP transistor. A second embodiment additionally includes a second PNP transistor having an emitter coupled to the select line and a collector coupled to said second supply voltage terminal for removing charge stored on the select line.
摘要:
A majority logic gate is comprised of a plurality of depletion mode switching devices and includes Schottky diodes for both level shifting and clamping the high logic level output voltage to ground. A plurality of MESFET input devices each have their gate electrode coupled to one input of the majority logic gate. Each MESFET input device has a source coupled to ground and a drain coupled to a current load device. The voltage level at the drain at each of the input devices changes from a logical "0" to a logical "1" state depending upon the number of inputs which are at a logical "1" level. The drain voltage is then level shifted down. The high logic level output voltage is clamped to ground by means of two Schottky diodes the first of which has a cathode coupled to ground and an anode coupled to the anode of the second diode, the cathode of the second diode being coupled to the output of the circuit.
摘要:
An integrated circuit is disclosed which includes a charge pump adapted for biasing the substrate of a monolithic integrated circuit containing bipolar transistors. An oscillator operating under the control of a control input provides pulsed output signals for driving a diode-capacitor voltage multiplier network which generates a substrate bias voltage. A feedback network including a zener diode senses the substrate voltage, and switching action of the zener diode operates to selectively enable and disable the oscillator for regulating the substrate bias voltage.
摘要:
A low voltage submicron CMOS circuit (10) for providing an output bandgap voltage (V.sub.BG) that is substantially independent of temperature and power supply variations has been provided. The CMOS circuit utilizes parasitic transistors (28-30) to create a delta voltage that has a positive temperature coefficient across a differential pair of NMOS transistors (14, 16). This delta voltage is then converted into differential currents which are amplified and mirrored and summed together to provide an output current (I.sub.O) that has a positive temperature coefficient. This output current is then passed through a series network including a resistor element (52) and a parasitic PNP junction transistor (31) to provide a bandgap voltage of 1.2 volts wherein the voltage across the resistor element has a positive temperature coefficient and the voltage across the parasitic PNP junction transistor has an inherent negative temperature coefficient.
摘要:
A source terminated transmission line driver circuit having an output coupled to a transmission line through a resistor is provided. The driver circuit has a gate circuit for providing first and second signals and a pulse generator circuit responsive to the second signal of the gate circuit for providing a pulse current at an output when the second signal is switching from a first logic state to a second logic state and for otherwise providing a quiescent current at the output. The driver circuit also has a first circuit responsive to the first output signal of the gate circuit for sourcing current to the output of the source terminated transmission line driver circuit, the first circuit being responsive to the second output signal of the gate circuit for sinking an adjustable current at the output of the source terminated transmission line driver circuit. The first circuit has a first transistor having a collector, a base and an emitter, the emitter being coupled to the output of the source terminated transmission line driver circuit, the base being coupled to receive the first signal of the gate circuit, and the collector being coupled to the first supply voltage terminal, a second transistor having a collector, a base and an emitter, the emitter of the second transistor being coupled to the output of the source terminated transmission line driver circuit, the base of the second transistor being coupled to the output of the pulse generator circuit, the collector being coupled to a second supply voltage terminal, a third transistor having a collector, a base and an emitter, the collector of the third transistor being coupled to the first supply voltage terminal, the base of the third transistor being coupled to the base of the first transistor, and a fourth transistor having a collector, a base and an emitter, the collector and base of the fourth transistor being coupled to the emitter of the third transitor, the emitter of the fourth transistor being coupled to the base of the second transistor.
摘要:
A circuit is provided that generates a predetermined regulated voltage between first and second terminals that is positioned between first and second power supply voltage rails wherein the predetermined regulated voltage is substantially independent of temperature and power supply variation. The circuit includes a bandgap circuit for providing a predetermined reference potential that is substantially independent of temperature and power supply variation. A resistive circuit provides first and second voltages which are referenced with respect to the first supply voltage rail. A level translator circuit translates the second voltage provided by the resistive circuit to a third voltage which is referenced with respect to the second supply voltage rail. First and second operational amplifier circuits are provided for respectively transferring the first and third voltages respectively to first and second terminals wherein a voltage developed between the first and second terminals is substantially equal to the predetermined reference voltage of the bandgap circuit.
摘要:
A circuit is described that provides a quick charge and discharge of a row of memory cells. A first transistor has its collector-emitter path coupled between a first voltage and a row of memory cells, and a base coupled to an input terminal. A second transistor has its collector-emitter path coupled to the first voltage by a resistor and to a voltage level setting device, and a base coupled to the input terminal. A third transistor has its collector-emitter path coupled between the row of memory cells and a second voltage, and a base coupled to a voltage level shifting device. As the row of memory cells are selected, the third transistor becomes less conductive, thereby sinking less current from the row of memory cells and allowing the inherent capacitance of the row of memory cells to charge more quickly. As the row of memory cells are deselected, the third transistor becomes more conductive, thereby sinking more current from the row of memory cells and discharging the inherent capacitance more quickly.
摘要:
A voltage level translator circuit is provided that translates an input voltage referenced to an ECL supply voltage V.sub.CC to a voltage referenced to a TTL supply voltage V.sub.EE independent of power supply voltage variations. A first and a second embodiment have reference circuits coupled to receive a data input signal for providing a single signal referenced to a first supply voltage terminal to a current mirror. An output circuit is coupled to the current mirror for providing an output signal referenced to the second supply voltage terminal. A third embodiment has a reference circuit coupled to receive a data input signal for referencing a voltage on a first supply voltage terminal to a voltage on a second supply voltage terminal. A voltage setting circuit is coupled to the reference circuit for setting a voltage within the reference circuit. An output circuit is coupled to the voltage setting circuit for providing an output voltage referenced to a voltage on the second voltage terminal and independent of variations in supply voltages.
摘要:
An integrated circuit power supply interconnection technique is disclosed having a highly doped, low resistivity substrate for distribution of the integrated circuit's most positive supply voltage. The substrate functions as the most positive voltage point and accomodates devices that are normally connected directly to this most positive supply voltage. A dielectric buried layer overlies a portion of the substrate and isolates the substrate supply voltage from devices that are not connected directly to the most positive supply voltage.