Highly linear bootstrapped switch with improved reliability

Abstract

Circuits, methods, and apparatus that provide bootstrapped switches having improved reliability. One example improves the reliability of a discharge transistor connected to discharge the gate of a switch transistor by decreasing its operating voltage during the discharge. This example provides a discharge transistor having a first source-drain region connected to a gate of a switch transistor. Since the gate of the switch transistor can reach high voltages, if the discharge transistor's second source-drain region is instantaneously tied to ground when the switch's gate is discharged, the discharge transistor's reliability can be degraded due to hot-electron effects. Accordingly, instead of being connected to ground—or an intermediate node that quickly reaches the ground potential during gate discharge—the second source-drain region of the discharge transistor is coupled to an intermediate node that discharges to ground at a slower rate.