CMOS output stage
Granted: October 8, 1991
Patent Number:
5055796
A CMOS output amplifier having a symmetrical output and a high ratio of output drive current to quiescent current. The amplifier uses first and second complementary devices connected in series between power supply connections with the output taken from the connection between the two devices. The input to the output stage is provided to the gate of the first device and to the gate of a third device of the same type as the second device, the source of the third device being maintained at a…
Bandgap voltage reference
Granted: September 24, 1991
Patent Number:
5051686
A bandgap voltage reference of a unique design is disclosed. The reference utilizes a pair of transistors operating at different current densities to provide a current component through a resistor at the .DELTA.V.sub.BE of the two transistors. A second current component through the resistor is provided through another resistor connected to the common emitter connection of another pair of transistors, the collectors of the last named pair of transistors each being connected to one input…
Buried zener diode
Granted: June 25, 1991
Patent Number:
5027165
An improved zener diode formed in a semiconductor wafer having a primary surface, the zener diode having a PN junction buried beneath the surface. The diode includes a pair of spaced contacts on the surface, the first located on one region and the second located on another laterally spaced region of the surface, to establish a current path through the diode. A replica device is formed on the same wafer generally replicating the physical dimensions of the zener diode. The replica device…
Integrated dual charge pump power supply and RS-232 transmitter/receiver
Granted: March 12, 1991
Patent Number:
4999761
A monolithic integrated circuit containing an inverting/non-inverting voltage doubler charge pump circuit is disclosed for converting a unipolar supply voltage to a bipolar supply voltage of a greater magnitude. A dual-collector lateral junction transistor, formed during the conventional CMOS processing steps used to fabricate the MOS switches, is connected as a voltage clamp between a ground potential and the two bipolar DC output lines of the power supply circuit to assure correct…
Integrated dual charge pump power supply and RS-232 transmitter/receiver
Granted: January 30, 1990
Patent Number:
4897774
A monolithic integrated circuit containing an inverting/non-inverting voltage doubler charge pump circuit is disclosed for converting a unipolar supply voltage to a bipolar supply voltage of a greater magnitude. The unipolar input voltage is placed across a first external transfer capacitor by a first set of MOS switches during a first time period. The unipolar input voltage source is placed in series with the first transfer capacitor and this series combination of voltages is placed…
High speed low gain stable amplifier
Granted: August 22, 1989
Patent Number:
4859963
The present invention is a high speed, low gain stable amplifier. The amplifier is for amplifying an input signal and providing an output signal to a known, fixed load. The amplifier has a first stage that is a differential amplifier that amplifies the input signal. The amplifier then has a second stage which is a push pull transconductance stage which operates at a low gain (approximately unity gain), and the transconductance of the push pull transconductance stage is approximately…
Programmable universal active filter
Granted: August 15, 1989
Patent Number:
4857778
The invention relates to a microprocessor-programmable, universal active filter. The filter has an input section, an operational amplifier with two input nodes, a bandpass section, a lowpass section and control circuitry which, under clock control, periodically brings one of the inputs of the operational amplifier to within a low, d.c. offset voltage, approaching zero volts, of the other input. The output of the lowpass filter section is coupled to the input of the bandpass filter…
CMOS amplifier/driver stage with output disable feature
Granted: July 11, 1989
Patent Number:
4847522
The invention relates to an output circuit capable of producing an output signal which may be disabled, leaving the output terminal in a high impedance state capable of being driven externally to a voltage significantly outside the bounds of the output circuit power supply. The output circuit of the invention includes two terminals adapted to be connected to a power supply capable of providing a supply voltage. The output circuit includes an MOS transistor having a substrate, source and…
Integrated AC to DC power supply
Granted: April 4, 1989
Patent Number:
4819147
An integrated off-line AC to DC power supply is disclosed. Alternating current (AC) line voltage is supplied (optionally) to an AC voltage to current converter and then (optionally) to a voltage limiter and rectifier which utilizes both MOS devices and inherent junction devices as either a full or half wave rectifier. The rectifier output is supplied to a series-pass junciton device voltage regulator or a regulator which has pre-set voltage output or user-selectable voltage output.
Bipolar lateral pass-transistor for CMOS circuits
Granted: March 14, 1989
Patent Number:
4812891
A bipolar lateral pass-transistor is disclosed for use in MOS integrated circuits. The transistor includes a semiconductor substrate of a first conductivity type covered by an epitaxial layer, a first region of a second conductivity type disposed in the epitaxial layer at a first doping level to a depth of less than the depth of said epitaxial layer, a second region of said conductivity type spaced apart from and surrounding said first region and extending approximately the entire depth…
Integrated dual charge pump power supply and RS-232-transmitter/receiver
Granted: February 28, 1989
Patent Number:
4809152
A monolithic integrated circuit containing an inverting/non-inverting voltage doubler charge pump circuit is disclosed for converting a unipolar supply voltage to a bipolar supply voltage of a greater magnitude. The unipolar input voltage is placed across a first external transfer capacitor by a first set of MOS switches during a first time period. The unipolar input voltage source is placed in series with the first transfer capacitor and this series combination of voltages is placed…
Precision operational amplifier
Granted: February 21, 1989
Patent Number:
4806875
The precision operational amplifier of the invention has at least two stages, a first input differential stage and a second high gain stage having its input coupled to the output of the first stage. A digital control circuit coupled to the output of the second stage is used to supply a correction signal to the first stage, the correction signal being calculated to compensate for the offset voltage of the first stage. A digital representation of the correction signal is stored so that it…
Programmable, universal filter with self biasing
Granted: January 31, 1989
Patent Number:
4801888
The invention relates to a self-biasing, programmable, universal active filter having an input section which includes an operational amplifier. The amplifier has one output and two input terminals. A first capacitor has one of its terminals coupled to a first of the input terminals of the amplifier and the other terminal serving as an input node to the filter. The second capacitor is coupled between the same input terminal and the output terminal. The filter has a bandpass section having…
Apparatus for pre-defining circuit characteristics
Granted: January 10, 1989
Patent Number:
4797569
An integrateable circuit is disclosed which allows selection between pre-defined and user-defined characteristics. The circuit utilizes a single input terminal for both selection and definition by a user. In a preferred embodiment, a comparator senses whether a user-supplied voltage at this input terminal is at a logic low level or not. If the voltage at this input terminal is at a logic level low, an internal voltage proportional to a pre-defined characteristic is enabled. If the…
Integrated dual charge pump power supply including power down feature and rs-232 transmitter/receiver
Granted: January 10, 1989
Patent Number:
4797899
A monolithic integrated circuit containing an inverting/non-inverting voltage doubler charge pump circuit is disclosed for converting a unipolar supply voltage to a bipolar supply voltage of a greater magnitude. The unipolar input voltage is placed across a first external transfer capacitor by a first set of MOS switches during a first time period. The unipolar input voltage source is placed in series with the first transfer capacitor and this series combination of voltages is placed…
Integrated dual charge pump power supply and RS-232 transmitter/receiver
Granted: October 11, 1988
Patent Number:
4777577
A monolithic integrated circuit containing an inverting/non-inverting voltage doubler charge pump circuit is disclosed for converting a unipolar supply voltage to a bipolar supply voltage of a greater magnitude. The unipolar input voltage is placed across a first external transfer capacitor by a first set of MOS switches during a first time period. The unipolar input voltage source is placed in series with the first transfer capacitor and this series combination of voltages is placed…
Integrated full-wave rectifier circuit
Granted: October 11, 1988
Patent Number:
4777580
A full-wave rectifier circuit is disclosed having two AC input terminals each having connected to it the anode end of a diode equivalent device. The cathode ends of each of the diode equivalent devices are connected together to a positive DC output terminal. Each AC input terminal also has connected to it one end of a switching device. The other ends of each of the switching devices are connected together to a negative DC output terminal. The control means of the switching devices are…
Apparatus for pre-defining circuit characteristics
Granted: June 21, 1988
Patent Number:
4752700
An integrateable circuit is disclosed which allows selection between pre-defined and user-defined characteristics. The circuit utilizes a single input terminal for both selection and definition by a user. In a preferred embodiment, a comparator senses whether a user-supplied voltage at this input terminal is at a logic low level or not. It the voltage at this input terminal is at a logic level low, an internal voltage proportional to a pre-defined characteristic is enabled. If the…
Integrated half-wave rectifier circuit
Granted: October 13, 1987
Patent Number:
4700286
An integrated off-line half-wave rectifier commonly connected to one side of the AC line at one of its output terminals is disclosed. An equivalent diode device passes current to the output during a positive AC input half cycle. A comparator senses the negative half cycle and turns on a switching device to conduct current between the two AC input terminals during that cycle.
Integrated dual charge pump power supply and RS-232 transmitter/receiver
Granted: July 7, 1987
Patent Number:
4679134
A monolithic integrated circuit containing an inverting/non-inverting voltage doubler charge pump circuit is disclosed for converting a unipolar supply voltage to a bipolar supply voltage of a greater magnitude. The unipolar input voltage is placed across a first external transfer capacitor by a first set of MOS switches during a first time period. The unipolar input voltage source is placed in series with the first transfer capacitor and this series combination of voltages is placed…
