A 6-GHz ROM suitable for DDFS application in GaAs HBT technology

• 来源期刊: 科学通报(英文版)
• 学科: 工学
• 年，卷（期）: 2011,（21）
• 页码范围: 2291-2296
• 页数: 6页
• 分类号: TN74
• 语种: 中文

摘要

Read-only memory (ROM) is widely implemented as a phase-to-amplitude mapping block in direct digital frequency synthesizers (DDFS).This paper derives an equivalent model for the ROM in a DDFS to analyze and reduce the access time that is critical to the performance of the DDFS.Moreover,the signal skew observed in the simulation waveform is illustrated.The proposed 64*3-bit ROM is integrated as a part of an 8-bit DDFS,which operates functionally at 6 GHz.Measurement results demonstrate the improvement in the spur free dynamic range.