Patent ID: 7372739
Filing Date: 2008-05-13
Classification: G11C

Abstract:
1. A voltage generator for generating an auxiliary voltage for use in a voltage generation and regulation circuit having a negative voltage pump that generates a negative voltage, a positive voltage pump that generates a positive voltage, an enable signal that enables the generation of the negative and positive voltages, and a plurality of discharge paths, each coupled to a different voltage pump, the discharge paths experiencing one of a plurality of discharge phases, the voltage generator comprising: output control logic that controls output of a discharge rate control signal; a plurality of NMOS transistors coupled together serially in a diode-like fashion, one end of the plurality of NMOS transistors coupled to and discharging the negative voltage when the plurality of NMOS transistors are turned on; a low voltage enabling transistor, coupled to the enable signal, for enabling the voltage generator in response to the enable signal; a first voltage insulating transistor, coupled between the low voltage enabling transistor and the plurality of NMOS transistors, a first node formed at the junction of the first voltage insulating transistor and a remaining end of the plurality of NMOS transistors having a voltage that rises in response to the low voltage enabling transistor being turned on; a first voltage enabling transistor coupled between V a second voltage insulating transistor coupled between the first node and the output control logic forming a second node, a control gate of the second voltage insulating transistor coupled between two of the plurality of NMOS transistors; and a second voltage enabling transistor coupled between V