Patent ID: 8030979

Claim:
A device comprising: a reference voltage generating unit configured to generate a uniform reference voltage in response to a bias voltage; a bias voltage generating unit configured to generate the bias voltage; and a start-up circuit, after activating the bias voltage generating unit by receiving a first supply voltage, configured to cancel a change of the first supply voltage to maintain a separation from the bias voltage generating unit, wherein the bias voltage generating unit comprises: a 4 th MOS transistor having a source and drain connected to the first supply voltage and the bias voltage, respectively; a 5 th MOS transistor having a gate connected to the gate of the 4 th MOS transistor and a source connected to the first supply voltage; a 6 th MOS transistor having a drain and source connected to the bias voltage and the reference potential, respectively; a 4 th resistor having one side connected to the reference potential; and a 7 th MOS transistor having a gate connected to the gate of the 6 th MOS transistor, a drain connected to the drain of the 5 th MOS transistor and a source connected to the other side of the 4 th resistor.