Bang-bang architecture

A method comprising:

• receiving a first signal in a control circuit responsive to an indication that a frequency of a voltage controlled oscillator (VCO) is different than a frequency of incoming data to a receiver including the VCO;
• generating a first control signal having a current value responsive to the first signal;
• and
• providing the first control signal to a first bias node of the VCO to adjust the VCO frequency in accordance with a change in a bias current coupling ratio between a first bias current and a second bias current, the first bias current including the first control signal.

A system comprising:

• a clock and data recovery (CDR) circuit including:
• a detector to receive incoming data and a clock signal from a tank oscillator, the detector to generate first and second signals indicative of a frequency relationship between the incoming data and the clock signal;
• a controller coupled to receive the first and second signals from the detector and to generate a first adjustable current and a second adjustable current responsive thereto;
• and
• the tank oscillator to receive the first and second adjustable currents and to generate the clock signal having a frequency according to a ratio between a first bias current including the first adjustable current and a second bias current including the second adjustable current;
• and
• an optical-to-electrical converter coupled to the CDR circuit to provide the incoming data to the CDR circuit.