A CMOS Analog Correlator-Based Painless Nonenzymatic Glucose Sensor Readout Circuit

An analog correlator-based readout circuit for amperometric glucose electrochemical biosensors is designed and implemented in 0.35-
$\mu{\rm m}$
CMOS process. The readout circuit offers lower noise and wider dynamic range compared with the conventional transimpedance amplifier architecture. The operational amplifier achieves a 118.3-dB gain and 47.3
$^{\circ}$
phase margin. The readout circuit dc response for input range of 5–30
$\mu{\rm A}$
gives a linear output voltage range of 0.21–1.38 V. The total output rms noise is measured to be 6.6 m
${\rm V}_{\rm rms}$
. It is applied for a microneedle glucose sensor and has a mean error of 1.6% and consumes 5.1 mW of power. The total area of the proposed readout circuit is 300
$\mu{\rm m}\times\,$
167
$\mu{\rm m}$
.