Patent ID: 7756266

Claim:
A device for voltage-noise rejection and fast start-up, applicable to suppressing noise in a voltage source, said device comprising: a low-pass filter connected to said voltage source for filtering out high-frequency noise and producing a DC-only voltage output, where DC denotes direct current; a voltage-controlled switch connected in parallel with said low-pass filter and bypassing said low-pass filter during start-up; and an auxiliary star-up element connected to said DC-only voltage output and providing a voltage to said voltage-controlled switch for voltage control; wherein said auxiliary start-up element further comprises: a voltage-controlled current source, connected to said DC-only voltage output to convert said voltage output to a current; a load, connected to an output of said voltage-controlled current source and a ground end to convert said current from said voltage-controlled current source to a voltage; and a threshold voltage detector for comparing said voltage of said load with a threshold.