Abstract: Circuitry comprises a high voltage rail providing a high voltage level corresponding to a higher voltage domain, an intermediate voltage source, a low voltage rail, and devices that operate in a lower voltage domain. First devices in an upper voltage region are powered between the high voltage rail and an intermediate voltage rail powered by the intermediate source. Second devices in a lower voltage region are powered between the intermediate and low rails. On power up, the intermediate source is powered before the high voltage rail. An isolating circuit connects the intermediate source to a node when the high voltage rail is powered and isolates the node from the intermediate source when the high voltage rail is not powered to impede current flow from the intermediate source to the high voltage rail.

Abstract: An apparatus is disclosed for receiving input signals in a first higher voltage domain and for generating and outputting signals in a second lower voltage domain, said apparatus comprising: an input pad; output circuitry, said output circuitry being configured to switch to output a first predetermined value in response to a rising input signal exceeding an upper threshold value and to switch to output a second predetermined value in response to a falling input signal falling below a lower threshold value; a first input path; a second input path; and a controllable connecting path between said first and second inputs.

Abstract: Circuitry is disclosed that comprises: a high voltage rail for providing a high voltage level corresponding to a first higher voltage domain; an intermediate voltage source, a low voltage rail; and a plurality of devices configured to operate in a second lower voltage domain; said circuitry being configured such that a first set of said plurality of devices are arranged in an upper voltage region where they are powered between said high voltage rail and an intermediate voltage rail powered by said intermediate voltage source and a second set of said plurality of devices are arranged in a lower voltage region where they are powered between said intermediate voltage rail and said low voltage rail, said circuitry being configured such that on power up said intermediate voltage source is powered before said high voltage rail, said circuitry further comprising: an isolating circuit arranged in said upper voltage region, said isolating circuit comprising at least one switching device for connecting said intermediat

Abstract: An apparatus is disclosed for receiving input signals in a first higher voltage domain and for generating and outputting signals in a second lower voltage domain, said apparatus comprising: an input pad for receiving said input signals in said first higher voltage domain; output circuitry comprising a plurality of devices arranged between a high voltage source of said second lower voltage domain and a low voltage source, said plurality of devices being arranged in a first set and a second set, said first set being arranged between said high voltage source and said output and said second set being arranged between said output and said low voltage source, said output circuitry being configured to switch to output a first predetermined value in response to a rising input signal exceeding an upper threshold value and to switch to output a second predetermined value in response to a falling input signal falling below a lower threshold value; a first input path for sending said received input signals to a first inp