Abstract:
A new silicon realization of an ultra-low-voltage and ultra-low-power differential-difference amplifier (DDA) is presented in this paper. The circuit combines the idea of...Show MoreMetadata
Abstract:
A new silicon realization of an ultra-low-voltage and ultra-low-power differential-difference amplifier (DDA) is presented in this paper. The circuit combines the idea of non-tailed bulk-driven differential pairs with a partial positive feedback used for voltage gain boosting. The DDA operates from VDD ranging from 0.3 to 0.5 V. For a 0.3-V version, the circuit provides measured DC voltage gain larger than 60 dB, the GBW product of 1.85 kHz, PSRR of 57 dB and the average slew-rate of 1.55 V/ms at 20 pF load capacitance, while consuming only 22 nW of power. An instrumentation amplifier based on the proposed DDA showed the THD of 0.5 % for Vin = 50 mVpp, and the 3-dB bandwidth of 750 Hz with the voltage gain of 2 V/V. The circuit has been fabricated in a standard n-well 0.18 μm CMOS process from TSMC. Chip test results agree with simulations. A special design procedure has also been developed that allows the circuit to be optimized under such extreme supply conditions.
Published in: IEEE Transactions on Circuits and Systems I: Regular Papers ( Volume: 66, Issue: 2, February 2019)