A new mismatch-insensitive 1.5-bit MDAC with unity feedback-factor and enhanced performance

In this paper a novel and mismatch-insensitive 1.5-bit MDAC is proposed. This circuit combines three main techniques that lead to a simulated reduction of the power dissipation of the order of 4 times, when compared to the conventional 1.5-bit MDAC circuit. Simulations also have shown that the proposed 1.5-bit MDAC is capable of achieving an SNDR of around 74 dB, i.e. compatible with 12 bits, corresponding to a 25 dB (4 bits) improvement when compared to the classic 1.5-bit MDAC. It is worth noticing that these results are achieved with a low gain, poor linearity and noisy residue amplifier, as all these innacuracies are cancelled thanks to the techniques employed.