P.A. Kondratovich1, Yu.E. Korchagin2, K.D. Titov3

1−3 Voronezh State University (Voronezh, Russia)

Comparators are key blocks in modern analog-to-digital converters (ADCs). Their resolution and speed affect the performance of the entire system. The most significant indicator of their performance quality is still the value of its zero offset. The aim of the work is to design a fully differential comparator with dynamic compensation of its zero offset. The basic principles and techniques of dynamic compensation of the comparator zero offset are described. A fully differential comparator with dynamic compensation of its zero offset (DOC, dynamic offset cancellation) is realized. The results of circuit modeling and measurements of finished samples are presented. The comparator was used in a serial approximation analog-to-digital converter (SAR ADC).

Kondratovich P.A., Korchagin Yu.E., Titov K.D. Comparator with dynamic offset compensation. Nanotechnology: development and applications – XXI century. 2023. V. 15. № 2. P. 29−37. DOI: https://doi.org/10.18127/j22250980-202302-03 (in Russian)

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