公开(公告)号：US08531214B2

公开(公告)日：2013-09-10

申请号：US13744821

申请日：2013-01-18

Applicant: MediaTek Inc.

Inventor： Shang-Ping Chen ,  Ping-Ying Wang

IPC: H03D3/24

CPC classification number: H03B19/00 ,  H03L7/081 ,  H03L7/1976

Abstract: Spread spectrum generators and methods are disclosed. In one implementation, a spread spectrum clock generator includes a phase locked loop generating an output clock according to a first clock and a second clock; a delay line coupled between the first clock and the phase locked loop; a modulation unit providing a modulation signal to control the delay line thereby modulating phase of the first clock, such that frequency of the output clock generated by the phase locked loop varies periodically; a scaling unit scaling the modulation signal from the modulation unit according to a scaling ratio, and outputting to the delay line; and a calibration unit generating an output signal for controlling the scaling ratio.

Abstract translation: 公开了扩频发生器和方法。 在一个实现中，扩频时钟发生器包括根据第一时钟和第二时钟产生输出时钟的锁相环; 耦合在所述第一时钟和所述锁相环之间的延迟线; 调制单元，其提供调制信号以控制延迟线，从而调制第一时钟的相位，使得由锁相环产生的输出时钟的频率周期性变化; 缩放单元，根据缩放比例从调制单元缩放调制信号，并输出到延迟线; 以及生成用于控制缩放比的输出信号的校准单元。