Comparator applications

About: Comparator applications is a research topic. Over the lifetime, 2518 publications have been published within this topic receiving 26639 citations.

Susceptibility of CMOS Voltage Comparators to Radio Frequency Interference

Abstract: This paper deals with the susceptibility to RF interference (RFI) of common CMOS voltage comparators. Approximate nonlinear analysis and time-domain computer simulations are carried out to highlight the causes of the false commutations induced by the disturbances superimposed onto the nominal input signals. Through these investigations, it is shown that the response of voltage comparators to RFI depends on the comparator initial state. This effect is also confirmed by the results of measurements carried out on a CMOS voltage comparator embedded in a test chip. Based on this, a new voltage comparator that avoids false commutations induced by high-frequency disturbances is proposed.

Digitally adjustable quantization circuit

Abstract: Apparatus and methods are provided for converting an analog input signal to a digital output value. A quantization circuit comprises an input node and a comparator array, wherein each comparator of the comparator array is coupled to the input node. A voltage divider arrangement is coupled to the comparator array and configured to establish a respective threshold voltage for each comparator of the comparator array. The comparator array generates a digital code based on the input signal and the respective threshold voltage for each comparator. A control node is coupled to the voltage divider arrangement, wherein the control node and the voltage divider arrangement are cooperatively configured to adjust the threshold voltage for at least one comparator of the comparator array in response to a control signal at the control node.

Voltage comparator with reduced settling time

Abstract: An improved voltage comparator for use in waveform characterization and like applications is disclosed. The current drawn through two matched transistors connected to a source of current is measured to determine whether a reference signal applied to the base of a first reference transistor is greater or less than the signal to be measured applied to the base of the other transistor. Current is only drawn through the two transistors at times corresponding to desired sampling times, substantially eliminating differential heating effects. The comparator provides substantially reduced settling times, resulting in reduced distortion of the waveform.

A programmable dual hysteretic window comparator

Abstract: A programmable dual hysteretic window comparator is presented in this paper The comparator uses a cascoded flipped voltage follower (CASFVF), a high speed V-I converter, and a current comparator to enhance the response time and accuracy Moreover, the positive and negative hysteretic thresholds can be programmable, respectively Simulation results in 025-mum CMOS technology demonstrate the validity of the designed approach

Periodic signal detecting circuit including comparator circuit with variable threshold and varying time constant

Abstract: A periodic signal detecting circuit including a comparator compares a threshold voltage varying with a time constant and an engine speed signal from an electromagnetic pickup coil so as to generate an output. The time constant is varied in accordance with the switching operation of a diode switch which is turned on and off in accordance with the comparator output. When the switch is in off condition, the threshold voltage is varied with the time constant which is changed successively.