Power efficient fully differential low-voltage two stage class AB/AB op-amp architectures

New low-voltage two stage fully differential class AB/AB op-amp architectures with high slew rate are introduced. The proposed circuits are very compact. The output stage does not require a quiescent current control circuit. Simulations are shown verifying high slew rate and rail-to-rail operation with a single supply voltage of 1.5 V and 0.5 μm CMOS technology with threshold voltages close to 1 V. The proposed architectures can operate with sub-volt supplies and rail-to-rail output swing in 0.25 μm and 0.18 μm CMOS technologies.