New current conveyor design

A CCII can be described as a combined voltage-follower and current-follower. To date, the most successful ways to realise a current follower have been based on the use of current mirrors to sense the output current of a voltage follower. However, all these schemes employ an open loop arrangement in which the current mirror transfer accuracy is highly dependent on the employment of identical transistors, something which is not easily achieved using a standard monolithic IC process. Mis-matched transistors result in increased non-linear CCII behaviour and degrade its overall performance. In this paper we introduce a new design for a bipolar current conveyor which has been constructed around a new current balance technique with good impedance transformation properties developed specifically for the conveyor to over-come the previous non-linear performance of the current mirror used in current sensing section.