Class AB fully differential voltage followers

Two fully differential class AB voltage followers with essentially enhanced slew rate are introduced. One is based on the cross-quad cell. The second is based on the conventional voltage follower. Class AB operation with accurate control of the quiescent current and extended bandwidth is achieved in both cases with minimal additional circuitry, zero extra static power dissipation and without increasing supply requirements. Experimental results of a test chip fabricated in 0.5 mum CMOS technology show slew rate enhancement of over a factor 15 and large extension of the peak to peak input range.