Reconfigurable analogue systems: the pulse-based approach

The paper presents new research into programmable analogue and mixed signal VLSI. The reported advances are placed in context of commercially produced field programmable analogue arrays whose performance and limitations are discussed. The novel approach reported uses digital pulses to encode analogue signal information. This is done by modulating the width of a digital pulse. Two pulse width coding schemes are described. The operating of the signal processing scheme is outlined without recourse to detailed transistor level descriptions. Results from working prototype VLSI devices are produced demonstrating the capability of the technique for implementing analogue sampled data, mixed signal and continuous time processing circuits. The suitability of the technique to future VLSI technology trends is highlighted