Dual mode clock generator

A dual mode clock generator, comprising:

• a frequency controller for controlling generation of charge and discharge currents according to first and second currents in a first operation mode and recognizing an initial state and a normal state according to a soft start signal to control generation of charge and discharge currents according to a third current or a fourth current in a second operation mode;
• a current source unit for generating a charge current according the first current in the first operation mode and generating a charge current according to the third current or the fourth current in the second operation mode depending on an initial state and a normal state through the control of the frequency controller;
• a capacitor for charging a voltage according to the charge current generated by the current source unit;
• an oscillation controller for controlling switch-on or switch-off to maintain a charge voltage of the capacitor between the predetermined highest reference voltage and the predetermined lowest reference voltage;
• a switch coupled between a ground and a connection node formed between the current source unit and the capacitor, and controlling charging and discharging of the capacitor by performing an on/off operation through the ON or OFF control of the oscillation controller;
• and
• a current sink unit coupled between the switch and the ground to generate a discharge current according to the second current in the first operation mode and generate a discharge current according to the third current and the fourth current in the second operation mode depending on an initial state and a normal state and to discharge a charge voltage of the capacitor using the discharge currents through the control of the frequency controller.