Skyworks Solutions, Inc.
Apparatus and methods for protection against inadvertent programming of fuse cells

Abstract:

Apparatus and methods for protection against inadvertent programming of fuse cells are provided herein. In certain configurations, a fuse system includes a fuse protection diode, a fuse, a fuse programming transistor and a cascode transistor electrically connected in series between a cathode of the fuse protection diode and the fuse, a power supply pad electrically connected to an anode of the fuse protection diode and that receives a power supply voltage, and a biasing circuit powered by the power supply voltage and including a voltage regulator that generates a regulated voltage and a level shifter that provides a fuse programming signal to a gate of the fuse programming transistor. The level shifter controls the fuse programming signal with the power supply voltage in a first state of a control signal, and controls the fuse programming signal with the regulated voltage in a second state of the control signal.