Comparator applications

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

Frequency adaptive negative voltage generator

Abstract: A negative voltage generator for an integrated circuit includes a charge pump responsive to the current loading on its output terminal. The charge pump is connected to a comparator which compares the output node of the charge pump with a reference potential. The comparator provides an analog output signal to a variable frequency oscillator, which in turn controls the charge pump. Variations in current loading caused the comparator to make appropriate changes in the oscillation frequency.

ATE measurement technique for comparator threshold voltage

Abstract: A system and a method for testing a comparator include generating two triangular waveform segments having the same period and different amplitudes, inputting the two triangular waveform segments into a comparator, receiving an output of the comparator, and calculating threshold voltages of the comparator based on the output. A periodic waveform can also be generated with repeating triangular waveform segments having the same period and different amplitudes as input to the comparator.

Hiccup-mode current protection circuit for switching regulator

Abstract: A hiccup mode current protection circuit for switched mode power converters for high power applications is provided. The circuit features a comparator for comparing an indicating voltage to a reference voltage and outputting a control signal to a disabling input where the indicating voltage exceeds a predetermined voltage threshold. The control signal also causes a switch to reduce the reference voltage to ensure that the comparator continues to output the control signal regardless of a drop in the indicating voltage. The control signal is maintained by a comparator for only a predetermined time period such that the switch eventually returns the reference voltage to its pre-reduction state, allowing the comparator to discontinue outputting the control signal if the indicating voltage is below the predetermined voltage threshold.

Analog-to-digital flash converter for generating a thermometric digital code

Abstract: A flash analog-to-digital converter includes a bank of comparators with a differential output, generating a thermometric code, and a bank of three-input logic NOR gates. The converter has enhanced immunity to noise and reduced imprecisions by providing for a passive interface including a plurality of voltage dividers each connected between the noninverted output of a respective comparator and the inverted output of the comparator of higher order of the bank. A corresponding logic NOR gate of the bank has a first input coupled to the inverted output of the respective comparator, a second input coupled to the noninverted output of the comparator of higher order and a third input coupled to an intermediate node of the voltage divider.

A new offset measurement and cancellation technique for dynamic latches

Abstract: This paper introduces a new technique that uses a differential amplifier in closed-loop negative feedback configuration to measure the offset of a dynamic latch. This offset can then be stored and canceled using standard techniques, thus allowing gain reduction in the preamplifier stages in high-resolution comparators. A CMOS comparator was designed based on the proposed technique. The output of the comparator drives a 1 pF load capacitance and is held valid for at least 75% of the cycle. The performance of the comparator was simulated using HSPICE with the worst-case combination of differences as large as 10 mV between the thresholds of nominally identical transistors, where it achieved an offset of 400 /spl mu/V at a 40 MHz clock rate in 0.6 /spl mu/m CMOS technology while dissipating 1 mW from a 3.3 V power supply.