Apparatus for power-on disable in a multiple power supply system and a method therefor

A power-on disable module for an apparatus having multiple power supply signals, the power-on disable module comprising;

• a controller coupled to receive a plurality of power supply signals including at least a first power supply signal, a second power supply signal, and a third power supply signal and coupled to provide an enable override signal depending on a comparison of the power supply signals.

A data processing system comprising:

• first and second power supply signals;
• a controller coupled to receive the first and second power supply signals and coupled to provide a control signal depending on a value of the first power supply signal in relation to a value of the second power supply signal;
• wherein the data processing system is one of the group consisting of a microprocessor, a microcontroller, a circuit board, an embedded system, a wireless communications device, and a software model of a data processing hardware design.

A circuit for controlling an output signal, the circuit comprising:

• a control circuit coupled to receive a first power supply signal and a power-on reset signal derived from a second power supply signal, the control circuit further coupled to provide a control signal depending on a comparison of the first power supply signal and the power-on reset signal.