Abstract:
In order to reduce the delay between the zero passage of the input voltage and the switching of the output in an analog comparator, a second transistor (T2; T20) controlled by a reference potential (VR1; VR2) is connected with its output circuit between the input and the output of a first transistor (T1) which is controlled by the output of a comparator differential stage. The saturation of said first transistor can be prevented with such a circuit.
Abstract:
A voltage comparator produces a current output as a function of the differential input voltage. Three transfer functions are detailed. In the linear transfer mode the output varies linearly in the transition region and swings between zero and a well-defined current value. In a truncated response mode, the output is zero for zero differential input voltage, remains at zero for one input voltage polarity, and rises for the other polarity input linearly to a well-defined current value. In the folded response mode the output current is zero for zero differential input and rises linearly in the transition region to a well-defined current value for either polarity of differential input. While a CMOS form of construction is preferred, bipolar construction is also shown.
Abstract:
Integrated circuit systems and semiconductor devices for generating, transmitting, receiving and manipulating clock and/or data signals. Semiconductor device including clock circuit having FETs and clock driver circuit having BJT. System and devices may include translator circuit translating signals with lower voltage swing into signals with higher voltage swing and circuit block operating at higher voltage swing. Wiring networks for communicating signals between individual circuits or system components. Integrated circuit device can include a BJT having first base electrode comprising semiconductor material doped to first conductivity type formed on and in contact with surface of semiconductor substrate and separated from emitter electrode by separation space. First base region can be formed in substrate below emitter electrode and include first portion of substrate doped to first conductivity type. Second base region can be formed in substrate below separation space and can include second portion of substrate doped to first conductivity type.
Abstract:
A bias circuit (101) that provides biasing for a differential circuit (103). The bias circuit (101) includes first and second transistors (Q3, Q4), first and second impedance devices (R1, R2), a reference current source (201) and an amplifier (203). The first and second transistors (Q3, Q4) each have a control input and a current path coupled between a first node (V1) and ground, where the control inputs of the first and second transistors receive the differential signal (VIN). The impedance devices (R1, R2) are each coupled between a control input of one of the first and second transistors and a second node (V2). The reference current source (201) provides a reference current (IREF) for the first node (V1) and the amplifier (203) has an input coupled to the first node (V1) and an output coupled to the second node (V2). The transistors (Q3, Q4), (Q1, Q2) of the bias circuit and the differential circuit, respectively, may be matched, NPN bipolar junction transistors with emitters connected to ground. A filter capacitor (C1) may be coupled between the first node (V1) and ground and operates as a low pass filter.
Abstract:
Problems associated with using bipolar differential circuits over a wide common mode voltage range are solved using first and second amplifier circuits (3 and 5), respectively operating over first and second voltage sub-ranges. The low voltage differential signal (LVDS) (1) is applied across a pair of series connected resistors (7 and 9), and to the inputs of the amplifiers (3 and 5). The common mode voltage signal (11) is fed to the inputs of third and fourth amplifiers (15 and 17). The third and fourth amplifiers (15 and 17) ensure that the LVDS receiver has a constant linear transfer characteristic over the differential input signal range and over the full common mode range, especially over the amplifier transition region.
Abstract:
Current supply circuits (23), (24) having switching elements are inserted on the power supply side (31) and on the power return wire side (32) of a differential amplifier means (10) in a voltage comparator, and are turned on or off. This makes it possible to obtain a voltage comparator which intermittently operates at high speeds consuming a reduced amount of electric power.
Abstract:
A comparator circuit (40) which includes a differential pair of transistors (12, 14) forming differential inputs of the comparator and a voltage level shift circuit (24, 26) coupled in series connection path with the emitters of the pair of transistors. The voltage level shift circuit includes an additional (26) transistor having its collector-emitter path connected in series between an output of the comparator and the emitter of the first pair of transistors; a first diode coupled in a series- conduction path to the emitter of the second one of the pair of transistors and having an anode connected to the base of the additional transistor; and a second diode (42) coupled between the base and emitter of the additional transistor wherein the effective beta of the additional transistor is reduced to reduce the bias current that would otherwise flow through the first transistor when such transistor is rendered conductive by an applied differential input signal.