Microprocessor having fuse control and selection of clock multiplier

摘要

A microprocessor is provided having selective control features to determine its core-to-bus clock ratio. The microprocessor includes a fuse and buffer/control logic. The fuse, fabricated on the microprocessor's metalization or poly layer, can be blown with a laser during fabrication. When blown, the fuse provides a permanent state that prescribes a fixed core-to-bus clock ratio. The buffer/control logic is coupled to the fuse. The buffer/control logic accepts the permanent state and directs the microprocessor to set the core-to-bus clock ratio to a fix value, thus disabling control of the core-to-bus clock ratio via external clock ratio control signals.