A logarithmic level-crossing ADC

Abstract

A 3-bit logarithmic level-crossing analog-to-digital converter (LC-ADC) for biomedical applications is presented. Based on the feedback LC-ADC structure, the proposed circuit is realized by using logarithmic charge-scaling digital-to-analog converters. The circuit is designed and simulated with process parameters from a 0.35-μm CMOS technology and a 1.5-V power supply voltage. Process corner simulation results showed that the INL and DNL errors are within the range of +0.14/−0.09LSB and +0.14/−0.21LSB, respectively.