Advanced Micro Devices, Inc.
CLOCK SYNTHESIZER WITH INTEGRATED VOLTAGE DROOP DETECTION AND CLOCK STRETCHING

Abstract:

A clock synthesizer has integrated voltage droop detection and clock stretching. An oscillator of the clock synthesizer receives a control current from a digital to analog converter and generates an oscillator output signal. A droop detector and clock stretching circuit responds to a voltage droop of a supply voltage supplying circuits coupled to the oscillator output signal, to cause a portion of the oscillator control current to be diverted from the oscillator to thereby cause the oscillator to reduce the first frequency. The diversion can be accomplished through shunt circuits or a current mirror circuit.