DESIGN OF CONTINUOUS TIME CIRCUITS USING CURRENT MODE BUILDING BLOCKS

Abstract

The information being processed in electric networks may be denoted through node voltages or through branch currents. An analog circuit is termed as voltage mode (VM) circuit when the information is expressed through voltage levels at different nodes, whereas if branch currents represent the signal, the circuit are termed as a current mode (CM) circuit. Current mode processing has received significant attention in the field of analog circuit design due to advantages offered over voltage mode circuits. This has resulted in emergence of various current mode analog building blocks which is evident from vast available literature. Voltage differencing buffered Amplifier (VDBA) is an active block of relatively recent origin which uses voltage differencing as input stage. In circuit implementation of VDBA its transconductance (gm) can be controlled through bias current which helps in electronic tuning of design parameters of the applications build around this active block. This leads to ease of circuit integration. The VDBA, therefor, has evolved as a promising choice for analog applications and this has led the author to explore analog circuit designing using VDBA. A variety of VDBA implementations are available in literature but a VDBA providing high transconsuctance gain (gm) and bandwidth (BW) with low power consumption has not been explored and leads to a significant research gap. So a low power, high performance VDBA using differential flipped voltage followers is presented.