Analog implementation of spread spectrum frequency modulation in a programmable phase locked loop (PLL) system

  • US 6,798,302 B2
  • Filed: 05/03/2002
  • Issued: 09/28/2004
  • Est. Priority Date: 05/06/2001
  • Status: Active Grant
First Claim
Patent Images

1. A phase locked loop circuit comprising:

  • a signal generator; and

    a spread spectrum modulator coupled to the signal generator, wherein the spread spectrum modulator comprises at least one selector, wherein the at least one selector selects a plurality of voltage levels that correspond to a spread mode and percentage of spread for the spread spectrum modulator and further wherein the spread spectrum modulator receives a control voltage as an input and provides a spread spectrum control voltage to the signal generator in response to the control voltage.

View all claims

    Thank you for your feedback