A self-calibrated system on a chip includes a semiconductor substrate, at least one silicon intellectual property (SIP) circuit including dynamic random access memories (DRAMs), a calibration circuit, and a function circuit, a cyclic oscillator, and a control circuit. Each DRAM has a coarsely-tuned capacitance value and a coarsely-tuned resistance value. The calibration circuit has a finely-tuned capacitance value and a finely-tuned resistance value. The cyclic oscillator transmits an oscillating clock signal to the control circuit to choose and provide the coarsely-tuned capacitance value, the coarsely-tuned resistance value, the finely-tuned capacitance value and the finely-tuned resistance value for the function circuit, thereby adjusting a function parameter.