Voltage converter, storage device including voltage converter, and operating method of voltage converter

A voltage converter comprising:

• a first transistor connected between an input node and a switch node;
• a second transistor connected between the switch node and a ground node;
• an inductor connected between the switch node and an output node;
• a capacitor connected between the output node and the ground node;
• resistors connected with the output node, and configured to divide an output voltage of the output node to generate a feedback voltage;
• a comparator configured to compare the feedback voltage and a reference voltage to output a comparison signal;
• a mode control circuit configured to output a mode signal of a first level based on an amount of a load current supplied through the output node being less than or equal to a threshold and to output the mode signal of a second level based on the amount of the load current being greater than the threshold;
• a control logic circuit configured to generate a first control signal and a second control signal based on pulse frequency modulation based on the mode signal being at the first level and to generate the first control signal and the second control signal based on pulse width modulation based on the mode signal being at the second level;
• and
• a gate driver configured to control the first transistor and the second transistor in response to the first control signal and the second control signal.

A storage device comprising:

• a nonvolatile memory device;
• a controller configured to control the nonvolatile memory device;
• and
• a power management integrated circuit configured to supply an output voltage to the nonvolatile memory device and the controller,
• wherein the power management integrated circuit includes:
• a first transistor connected between an input node and a switch node;
• a second transistor connected between the switch node and a ground node;
• an inductor connected between the switch node and an output node from which the output voltage is output;
• a capacitor connected between the output node and the ground node;
• resistors connected with the output node, and configured to divide the output voltage to generate a feedback voltage;
• a mode control circuit configured to output a mode signal of a first level based on an amount of a load current being supplied through the output node is greater than a threshold and to output the mode signal of a second level based on the amount of the load current being less than or equal to the threshold;
• a control logic circuit configured to generate a first control signal and a second control signal based on pulse frequency modulation based on the mode signal being at the first level and to generate the first control signal and the second control signal based on pulse width modulation based on the mode signal being at the second level;
• and
• a gate driver configured to control the first transistor and the second transistor in response to the first control signal and the second control signal.