Title :
Class AB CMOS Operational Amplifiers with Very High Efficiency
Author :
Callewaert, L. ; Sansen, W.
Author_Institution :
Dept. Elektrotech., Katholieke Univ. Leuven, Heverlee, Belgium
Abstract :
A new, simple, yet very current efficient class AB amplifier principle is presented. When used as a differential input stage it features a settling time which is independent of the input signal, and a current efficiency superior to that of any conventional OTA. The same class AB stage can also be used as an output stage with a rail to rail output voltage swing, and a large drive capability. An amplifier with both input and output stages based on this new principle is presented. This amplifier features a gain bandwidth of 310 kHz and a settling time to 0.1% of 2.4 μs. It can drive a resistive load of 2500 Ohm in parallel with a capacitive load of 400 pF when operated on a 2.5 V/-2.5 V power supply, with a quiescent power consumption of only 285 μW.
Keywords :
CMOS analogue integrated circuits; low-power electronics; operational amplifiers; AB amplifier principle; bandwidth 310 kHz; capacitance 400 pF; capacitive load; class AB CMOS operational amplifiers; current efficiency; gain bandwidth; input signal; input stage; output voltage swing; power 285 muW; power consumption; resistive load; resistivity 2500 ohmm; voltage 2.5 V; Active filters; Capacitors; Cutoff frequency; Inverters; Low pass filters; Operational amplifiers; Resistors; Transconductance; Transconductors; Voltage;
Conference_Titel :
Solid-State Circuits Conference, 1989. ESSCIRC '89. Proceedings of the 15th European
Conference_Location :
Vienna
Print_ISBN :
3-85403-101-7
DOI :
10.1109/ESSCIRC.1989.5468139
