Selector-based random number generator and method thereof

A method of generating a random number, adapted to a random number generator comprising a selector, the method comprising:

• sweeping a configuration of a bias control signal among a plurality of configurations;
• generating an oscillation signal based on the configuration of the bias control signal;
• detecting an onset of the oscillation signal and outputting a lock signal upon a detection of the onset of the oscillation signal;
• and
• latching the oscillation signal to output a random number according to a trigger signal, wherein the trigger signal is asserted after the lock signal is outputted, and the configuration of the bias control voltage is locked according to the lock signal.

An operation method of a random number generator comprising an oscillation circuit, a control circuit, a dynamic header circuit, an oscillation detection circuit and a latch circuit, the operation method comprising:

• sweeping, by the control circuit, a configuration of a bias control signal among a plurality of configurations;
• generating, by the oscillation circuit, an oscillation signal according to the configuration of the bias control signal;
• detecting, by the oscillation detection circuit, an onset of the oscillation signal, and outputting, by the oscillation detection circuit, a lock signal upon a detection of the onset of the oscillation signal, wherein the configuration of the bias control signal is locked according to the lock signal;
• latching, by the latch circuit, the oscillation signal according to a trigger signal to output a random number, wherein the trigger signal is asserted after the lock signal is outputted by the oscillation detection circuit.