| 摘要 |
PURPOSE: A method for providing a replica bias voltage and a voltage controlled oscillator using the replica bias voltage are provided to steadily maintain difference between a replica bias voltage and a power voltage inputted to a delay cell by changing the replica bias voltage provided to the delay cell according to the power voltage. CONSTITUTION: A replica bias circuit(10) supplies a first replica bias voltage which limits a swing range of output signals of a plurality of delay cells(20) into a fixed range. The delay cell changes a delay between input signals and the output signals according to a control voltage. A switch(30) selectively delivers the first replica bias voltage of the replica bias circuit to a first node. An on and off state of the switch is controlled by a selection signal. The first node is connected to one end of a capacitor(40). A first power voltage is applied to the other end of the capacitor. A second replica bias voltage has the same voltage value as the first replica bias voltage in the on state of the switch. The second replica bias voltage is changed according to the first power voltage in the off state of the switch. |
