Self-adjusting clock doubler and integrated circuit clock distribution system using same

摘要

In one form, a clock doubler includes a switched inverter, an exclusive logic circuit, and a control signal generation circuit. The switched inverter has first and second control inputs for respectively receiving first and second control signals, a signal input for receiving a clock input signal, and an output. The exclusive logic circuit has a first input for receiving the clock input signal, a second input coupled to the output of the switched inverter, and an output for providing a clock output signal. A control signal generation circuit provides the first and second control signals in response to the clock output signal. The clock doubler may be used in a clock distribution circuit for an integrated circuit that also includes a phase locked loop for providing the input clock signals, and a plurality of clock sub-domains each having one of the clock doublers.

主权项

1. A clock doubler comprising:
a switched inverter having first and second control inputs for respectively receiving first and second control signals, a signal input for receiving a clock input signal having a first frequency, and an output for providing a selectively inverted clock signal in response to said first and second control signals; an exclusive logic circuit having a first input for receiving said clock input signal, a second input coupled to said output of said switched inverter for receiving said selectively inverted clock signal, and an output for providing a clock output signal at a second frequency double said first frequency; and a control signal generation circuit for providing said first and second control signals in response to said clock output signal.