Wideband current-mode absolute value circuits

Two wideband current-mode absolute value, or precision full-wave rectifier (PFWR), circuits have been designed and developed. They are transistor level based designs, ideally suited for ASIC realisation. The two different, architecture circuits are described. In the first design a comparator is used to control a current-steering circuit to achieve the required unipolar output response. The topology of the circuit exhibits high speed performance with minimum transients. The second design is a development from the first. The circuit has lower overall complexity and provides enhanced performance. It is based on an emitter-coupled common-collector, with a NPN Quasi-Darlington dynamic buffer. Both techniques show promising performance in terms of operating speed