ON THE DEVELOPMENT OF ANALOG SAMPLED-DATA SIGNAL-PROCESSING

This paper provides a historical perspective on the development of ana logue sampled-data signal processing circuits and systems. The evoluti on, role and current trends in the development of analogue sampled-dat a signal processing systems is surveyed. Firstly, the evolution of int egrated circuit based techniques, culminating in the ubiquitous switch ed-capacitor technique is traced. Then the role that analogue sampled- data systems play within the context of a general information processi ng environment is examined and the required characteristics are identi fied. Trends in silicon integrated circuit processing technology are s ummarised and their impact on sampled analogue circuits are identified . Finally, the application of analogue current-mode techniques, and in particular switched-currents, to overcome some of the limitations of previous voltage based approaches, is discussed.