Boost device for nonvolatile memories with an integrated stand-by charge pump

A clock generating stage comprising:

• a first acquisition means acquiring a first timing signal having a first frequency;
• a second acquisition means acquiring a second timing signal having a second frequency, different from said first frequency;
• a clock selection means having a first and a second signal input receiving respectively said first and said second timing signal and an output supplying an output signal having selectively said first or said second frequency;
• and
• a logic means connected to said output of said clock selection means and generating a transition phase between said first and said second frequency without spurious switching.

A boost device for nonvolatile memories comprising:

• a charge pump circuit having an input, a plurality of phase signal inputs, a first output of a first output stage and a second output of a second output stage wherein the first and second output stages are coupled in parallel;
• a phase generator circuit having a clock input and a plurality of phase signal outputs wherein the plurality of phase signal outputs are coupled to the plurality of phase signal inputs of the charge pump circuit;
• a clock generator circuit having a first clock timing signal input, a second clock timing input signal, a first pump enable signal input, a stand-by signal input, a second pump enable signal input, and a clock output wherein the clock output is coupled to the clock input of the phase generator;
• and
• a switch having first and second terminals wherein the first terminal is coupled to the first output, and the second terminal is coupled to the second output.

A method for controlling pumping action in a boost device having a charge pump, a first and second clock input signals, and a clock output signal, comprising the steps of:

• detecting a status change in a stand-by signal condition;
• generating a clock select signal to control the selection of the first or second clock input signals thereby coupling a selected clock signal to either the first or second clock input signal;
• detecting a first status change in a first and second enables signals;
• detecting a clock event in the selected clock signal;
• setting the clock output signal to the selected clock signal, upon the clock event of the selected clock signal;
• detecting a second status change in the first and second enable signals;
• and
• holding a present status of the clock output signal and storing the present status of the clock output signal, upon the second status change in the first and second enable signals.

A boost device, comprising:

• an input and a first output;
• a charge pump circuit including:
• a first output stage having an input node connected to the input and a first output node connected to the first output;
• a second output stage having an input node coupled to the input node of the first output stage, and an output node;
• and
• a switch coupled between the output nodes of the first and second output stages to thereby couple the output stages in parallel with each other.