Sandisk Corporation

Sandisk Technologies Inc.

Prajit Nandi

Jun Li

Mehrdad Mofidi

Sridhar Yadala

Techniques of operating a charge pump are described. The charge pump is connectable to receive a clock signal and a regulating voltage and provide an output voltage. The charge pump can have one or multiple stages, each of the stages will include a capacitor. During the charging phase, the regulating voltage is used to regulate the potential of the capacitor's bottom plate. During the boosting phase, the capacitor's top plate is connected to supply the output for the stage and the bottom plate is connected to receive the stage's input. Each stage will also have a set of switching elements, allowing the capacitor to be alternately connected in the charging and boosting phases. For the first stage, the input is derived from the clock signal, and for any subsequent stages, the input will be the output of the preceding stage. The last stage provides the output voltage of the pump.

Bottom plate regulation of charge pumps

Method for controlling voltage in a non-volatile memory system is provided. The method includes selecting a first input value for a voltage generator system operating in one of a plurality of modes, the first input value controlling a temperature dependent component of a voltage applied to a memory cell; and selecting a second input value for the voltage generator system operating in one of the plurality of modes, the second input value controlling a temperature independent component of the voltage applied to the memory cell. The temperature dependent component of the voltage applied to the memory cell and the temperature independent component of the voltage applied to the memory cell are controlled independently in response to the first input value and the second input value.

Method for controlling voltage in non-volatile memory systems

Method and system for controlling voltage and its temperature co-efficient in a non-volatile memory device having a plurality of programmable memory cells is provided. The system includes a temperature-dependent voltage generator for generating an output that is controlled independently by a first multiplier; a temperature-independent voltage generator having a constant output, wherein the constant output is controlled by a second multiplier; and an amplifier that receives the constant output of the temperature-independent voltage generator and the output of temperature-dependent voltage generator to generate a voltage that is applied to a memory cell for a read, and program-verify operation; wherein the temperature co-efficient and voltage applied to memory cells is controlled independently so that intrinsic temperature coefficient of the memory cell is substantially similar to temperature coefficient of the applied voltage.

Method and system for independent control of voltage and its temperature co-efficient in non-volatile memory devices

System for a non-volatile memory system is provided. The non-volatile memory system includes a voltage generator system operating in one of a plurality of modes for generating a voltage applied to a memory cell of the non-volatile memory system. For one of the plurality of modes, a first input value is selected for controlling a temperature dependent component of the voltage and a second input value is selected for controlling a temperature independent component of the voltage. The temperature dependent component of the voltage and the temperature independent component of the voltage are controlled independently in response to the first input value and the second input value.

System for controlling voltage in non-volatile memory systems

System and method for controlling voltage in a non-volatile memory system is provided. The system includes a voltage regulator that monitors an output voltage (VDD) and a mirror voltage (Vmirror). When the voltage VDD is greater than the voltage Vmirror beyond a threshold value, a control signal turns off a control transistor, which prevents the voltage VDD to increase beyond a certain value. The method includes comparing an output voltage (VDD) with a mirror voltage (Vmirror); and generating a control signal to turn off a control transistor if the voltage VDD is greater than the voltage Vmirror.

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Karnataka, India

Prajit Nandi