公开(公告)号：US6271731B2

公开(公告)日：2001-08-07

申请号：US37303597

申请日：1997-04-15

Applicant: ERICSSON INC

Inventor： KOSZARSKY CHRISTOPHER R

IPC: H03B1/00 ,  H03B5/12 ,  H03L7/099 ,  H03L7/10 ,  H03L7/18 ,  H03B5/08

CPC classification number: H03L7/18 ,  H03B5/1203 ,  H03B5/1231 ,  H03B5/1243 ,  H03B5/1262 ,  H03B2201/0291 ,  H03L7/099 ,  H03L7/10 ,  H03L2207/06

Abstract: A frequency synthesizer has a voltage controlled oscillator comprising a voltage controlled capacitor having a first terminal and a second terminal. A positive control voltage is applied to the first terminal of the voltage controlled capacitor and a negative control voltage is applied to the second terminal of the voltage controlled capacitor, causing the varactor to operate in a reverse biased state. A circuit for generating a negative control voltage is provided in a phase-locked loop circuit. The circuit includes a negative DC generator for generating a negative DC voltage from an AC signal, and a programmable variable attenuator for selectably attenuating the negative control voltage.

Abstract translation: 频率合成器具有压控振荡器，其包括具有第一端子和第二端子的压控电容器。 正压控制电压被施加到压控电容器的第一端，并且负控制电压被施加到压控电容器的第二端子，导致变容二极管以反向偏置状态工作。 用于产生负控制电压的电路设置在锁相环电路中。 该电路包括用于从AC信号产生负DC电压的负DC发生器和用于可选择地衰减负控制电压的可编程可变衰减器。