(IEEE, 2018) López Martín, Antonio; Garde Luque, María Pilar; Algueta-Miguel, Jose M.; Cruz Blas, Carlos Aristóteles de la; Carvajal, Ramón G.; Ramírez-Angulo, Jaime; Institute of Smart Cities - ISC
An enhanced single-stage folded cascode operational
transconductance amplifier able to drive large capacitive loads is
presented. Circuits that adaptively bias the input differential pair
and the current folding stage are employed, which provide class
AB operation with dynamic current boosting and increased gainbandwidth (GBW) product. Measurement results of a test chip
prototype fabricated in a 0.5-µm CMOS process show an increase
in slew rate and GBW by a factor of 30 and 15, respectively,
versus the class A version using the same supply voltage and bias
currents. Overhead in other performance metrics is small.
(IEEE, 2020) López Martín, Antonio; Algueta-Miguel, Jose M.; Garde Luque, María Pilar; Carvajal, Ramón G.; Ramírez-Angulo, Jaime; Institute of Smart Cities - ISC
A super class AB recycling folded cascode amplifier in 130 nm CMOS is presented. It combines for the first time adaptive biasing of the differential input pair, nonlinear current mirrors with current starving and dynamic biasing of the cascode transistors in the output branch. Measurements using a ±0.5V supply show slew rate and gain bandwidth product improvement factors of 26 and 112 versus the conventional topology for the same bias currents, yielding the highest combined FoM to date.
