A 480 mVpp Linear Input Range, Low Noise Transconductance Cell for Multi-Input Sensor Interface

This brief proposes a high-linear transconductance cell based on parallel source degeneration and differential flipped voltage followers (FVFs) with balance resistors. The prototype is implemented in a 180 nm BCD process, occupying a core area of 0.0298 mm2. Experimental result shows that the 1% total harmonic distortion (THD) linear input range is up to 480 mVpp with a 1.8 V voltage supply. The noise floor is 80.53 nV/
$\sqrt {\mathbf {Hz}}$
, and the integrated noise is 8.69
$\mu \text{V}_{\mathrm {rms}}$
within the bandwidth of 0.3-10 kHz. The proposed transconductance cell is applied to a multi-input sensor interface based on frequency division multiplexing (FDM), demonstrating its effectiveness and versatility in practical applications.