Voltage generator and memory device including the same

A voltage generator comprising:

• a timer configured to output a reset signal based on a reference time being elapsed;
• a plurality of oscillators configured to output a plurality of reference clock signals having a plurality of reference frequencies, respectively;
• and
• a plurality of charge pump blocks configured to
• generate a first clock signal based on a reference clock signal received from a connected oscillator among the plurality of oscillators,
• count a number of state transitions of the first clock signal until the reset signal is received, and
• perform an amplifying operation on an input voltage based on the number of state transitions,
• wherein a number of the plurality of charge pump blocks is greater than or equal to a number of the plurality of oscillators.

A memory device comprising:

• a cell array including a plurality of memory cells;
• and
• a voltage generator configured to generate an operating voltage applied to at least one memory cell among the plurality of memory cells,
• wherein the voltage generator includes:
• a charge pump configured to
• perform an amplifying operation on an input voltage based on a clock signal, and
• generate the operating voltage;
• a counting block configured to
• count a number of state transitions of the clock signal for a reference time, and
• control the charge pump based on the number of state transitions;
• and
• a timer configured to initialize the number of state transitions based on the reference time being elapsed.