We describe a photoreceptor circuit that can be used in massively parallel analog VLSI silicon chips, in conjunction with other local circuits, to perform initial analog visual information processing. The receptor provides a continuoustime output that has low gain for static signals (including circuit mismatches), and high gain for transient signals that are centered around the adaptation point...

In dc-to-dc conversion applications that require a large range of input andlor output voltages, conventional PWM converter topologies must operate at extremely low duty ratios, which limits the operation to lower switching frequencies because of the minimum ONtime of the transistor switch. This is eliminated in a new class of singletransistor PWM converters featuring voltage conversion ratios w...