A Complementary CMOS differential amplifier has automatic operating point adjustment (self-biasing) and the properties of a rail-to-rail amplifier. The CMOS differential amplifier uses folded cascodes and is considerably faster in operation than previous CMOS differential amplifiers, since it comprises a circuit element that ensures that, during the operation of the CMOS differential amplifier, all MOS FETs of the cascodes operate in their saturation range (that is not in their resistive range). The CMOS differential amplifier may be used in an input stage, a signal distribution circuit and a clock pulse distribution circuit.
A differential input/differential output converter circuit. The circuit comprises differential complementary input modules each comprising cross-coupled devices for biasing current mirror masters to a condition that increases the operating speed in response to a transition in the differential input signals. Certain current mirror masters are biased to a strong threshold condition and other current mirror masters are biased to a weak threshold condition responsive to a state of the differential input signals. According to another embodiment, the converter circuit further comprises a boost circuit capacitively coupled to the converter circuit for providing further speed improvements.
A low DC power rail-to-rail buffer amplifier is suitable for liquid crystal display application. The buffer amplifier comprises: a dc bias stage, a pair of complementary differential amplifiers, a second stage amplifier, and output stage. The dc bias stage is used for the dc bias of the differential amplifiers and the second stage to obtain a rail-to-rail operation. This buffer amplifier can be operated in the power supply ranges of 5.5 V to the breakdown voltage. Simulated results show that the circuit draws only 5.3 .mu.A static current.
An input buffer circuit achieving rail-to-rail operation maintains a uniform common mode output voltage even though an input signal having any voltage level is inputted. The input buffer circuit has a differential amplifier structure receiving two differential input signals. A first input part has a first inverter circuit into which a first differential input signal is inputted, and a second input part has a second inverter circuit into which the second differential input signal is inputted. The first inverter circuit has a first output node connected to a diode structure having an operating current twice the operating current of the first inverter circuit, and outputs a first output signal. Rail-to-rail operation is achieved, and a common mode output voltage is provided uniformly, with reduced current consumption.
A differential difference amplifier includes a first pair of differential input terminals and a second pair of differential input terminals. The differential difference amplifier has a pair of differential output terminals to output a voltage in relation to a difference between differential voltages at the first pair of differential input terminals and differential voltages at the second pair of differential input terminals.
A differential amplifier circuit in which an input offset voltage is very small. The differential amplifier circuit includes an input-stage differential amplifier section and a cascode-connected single-ended output section connected to the input-stage differential amplifier section. The input-stage differential amplifier section has a folded-cascode-connection. An inverted signal and non-inverted signal on the input side and output side, respectively, of the input-stage differential amplifier section are switched alternatingly in time-shared fashion by switches that are operated by two chopping clock signals of opposite phase.
