Title:
通信用半導体集積回路および携帯通信端末
Document Type and Number:
Japanese Patent JP4623507
Kind Code:
B2
Abstract:
The present invention provides a semiconductor integrated circuit for communication (radio frequency IC) capable of detecting and correcting variations in an amplitude loop band of a transmission circuit having a phase control loop and an amplitude control loop without using an external measuring apparatus. In a semiconductor integrated circuit for communication (radio frequency IC) including a transmission circuit having a phase control loop for controlling the phase of a carrier wave and an amplitude control loop for controlling the amplitude of a transmission output signal, a calibration circuit for detecting variations in a loop gain of the amplitude control loop and correcting the loop band is provided. The calibration circuit detects variations in a loop gain by comparing a feedback signal with an output signal of a modulation circuit while changing electric parameters of any of circuits on the amplitude control loop step by step, and corrects the loop band by changing characteristics of any of the circuits on the amplitude control loop in accordance with the detected variations.
Inventors:
Kenji Toyoda
Ryoichi Takano
Noriyuki Kurakami
Ryoichi Takano
Noriyuki Kurakami
Application Number:
JP2005119162A
Publication Date:
February 02, 2011
Filing Date:
April 18, 2005
Export Citation:
Assignee:
Renesas Electronics Corporation
International Classes:
H04L27/12; H03G3/30; H04B1/04; H04L27/20
Domestic Patent References:
| JP2004007445A | ||||
| JP2241135A | ||||
| JP11024705A | ||||
| JP2002016462A |
Foreign References:
| WO2004002098A1 |
Attorney, Agent or Firm:
Shizuyo Tamamura