Flash memory having dual supply operation

摘要

A flash memory device may operate from two supply voltages, one being provided externally, and the other being generated within the flash memory device from the external supply voltage. The flash memory device may be provided with a selectable-level buffer for interfacing with either low supply voltage or high supply voltage integrated circuits. To provide even greater flexibility, the flash memory device may be provided with the capability of receiving a second supply voltage from an external source, which may take precedence over the internally-generated second supply voltage or may be combined with the internally-generated second supply voltage.

主权项

1. A flash memory device operable at a first supply voltage while supporting Input/Output (“I/O”) interface operations with external circuits operable at either the first supply voltage or at a second supply voltage less than the first supply voltage, comprising:
a plurality of active terminals; a flash memory section; a control section coupled to the flash memory section; a selectable-I/O level buffer coupled to the control section and to the active terminals to communicate control and data signals externally of the flash memory device; a first supply voltage terminal for receiving a first supply voltage from an external voltage source; an internal power bus coupled to the first supply voltage terminal; and a supply voltage generator coupled to the internal power bus for generating an internal voltage less than the first supply voltage from the first supply voltage, and for furnishing from the internal voltage at an output thereof an output voltage at a level adapted to interface with external circuits operable at the second supply voltage; the selectable-I/O level buffer being coupled to the internal power bus and to the output of the supply voltage generator for selectively operating the active terminals at the first supply voltage or the output voltage.