Receiver circuitry and method for converting an input signal from a source voltage domain into an output signal for a destination voltage domain

Abstract

The present invention provides a receiver circuit and method for receiving an input signal from a source voltage domain and converting the input signal into an output signal for a destination voltage domain. The source voltage domain operates from a supply voltage that exceeds a stressing threshold of components within the receiver circuitry, and the receiver circuitry is configured to operate from the supply voltage of the source voltage domain. The receiver circuitry comprises first internal signal generation circuitry configured to convert the input signal into a first internal signal in a first voltage range, and second internal signal generation circuitry configured to convert the input signal into a second internal signal in a second voltage range. Signal evaluation circuitry establishes a logic high voltage threshold and a logic low voltage threshold dependent on the supply voltage, and employs the first and second internal signals in order to detect based on the logic high voltage threshold and logic low voltage threshold when the input signal transitions between a logic low level and a logic high level (in either direction). Output generation circuitry then generates the output signal in dependence on the detection performed by the signal evaluation circuitry. The first voltage range and the second voltage range are such that the first internal signal and second internal signal will not exceed the stressing threshold of components in the signal evaluation circuitry. The receiver circuitry is able to reliably detect transitions in the input signal in situations where the supply voltage of the source voltage domain exceeds the stressing threshold of the receiver's components, but without overstress of the receiver's components.