Single point modulator having a PLL circuit

US7453325B2 · kind B2 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Markus Hammes · Dinslaken, DE
• Giuseppe Puma · Bochum, DE
• Stefan Waasen · Sollentuna, SE

Key dates

• Filing date: Aug 12, 2004
• Grant date: Nov 18, 2008
• Expiry date: Jan 24, 2027

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03L7/1976
• WIPO field: Basic communication processes
• WIPO sector: Electrical engineering

Abstract

A single-point modulator (1) has a PLL circuit (2) and a programmable frequency divider (7) whose control connection is connected to a circuit branch for injecting a digital modulation signal (15) which is arranged in the feedback path of the PLL circuit (2). The circuit branch contains a sigma-delta modulator (9) which, in turn, has a digital filter (24) having a transfer function H(z). The noise transfer function NTF(z) of the sigma-delta modulator (9) is given by the function NTF(z)=1−H(z).