A new solution for an ultralow-voltage bulk driven (BD) asynchronous delta–sigma modulator is described in this paper. While implemented in a standard 0.18-µm CMOS process from the Taiwan Semiconductor Manufacturing Company and supplied with VDD = 0.3 V, the circuit offers a 53.3-dB signal-to-noise and distortion ratio, which corresponds to 8.56-bit resolution. In addition, the total power consumption is 37 nW, the signal bandwidth is 62 Hz, and the resulting power efficiency is 0.79 pJ/conversion. The above-mentioned features have been achieved employing a highly linear transconductor and a hysteretic comparator based on nontailed BD differential pair.
Software Implementation:
TANNER EDA
Advantages:
Less Quantization noise
Less complicated circuit with no required clock signals
Lower relative supply voltage
Less Harmonics in Output signals
Its improving linearity and consequently the resolution of ADSM
