A 500mV, 118nW, ∑Δ-Modulator ADC for Audio Detection in 28 nm FD-SOI

In this work a 500 mV supply voltage, low power, inverter-based
$\Sigma\Delta$
-modulator in 28 nm FD-SOI is presented. The discrete-time
$\Sigma\Delta$
-modulator is optimized for low power and is to be used in audio detection applications. The switched-capacitor integrators are designed using inverter-based amplifiers with a DC cancelling scheme to suppress DC offset. An optimization of the inverter-based amplifiers is shown taking advantage of the simple structure. The 2
^nd
-order
$\Sigma\Delta$
-modulator achieves a
$\mathrm{SNDR}_{\mathrm{peak}}=46\mathrm{dB}$
with an OSR of 32 and power consumption of 118nW.