Phase-locked circuit and radio communicating device

Abstract

Disclosed herein is a phase-locked circuit including: a phase-locked section including a voltage controlled oscillator having a capacitance bank and changing oscillation frequency according to voltage information, the phase-locked section phase-locking an oscillating signal of the voltage controlled oscillator to a reference signal; and a calibration section having a voltage correcting function for supplying an appropriate calibration voltage to the voltage controlled oscillator in performing frequency calibration for the voltage controlled oscillator; the calibration section including a counter circuit, a first storage circuit and a second storage circuit, a comparator circuit, a control circuit, a voltage generating circuit, and a processing circuit.

Description

technical field [0001] The present disclosure relates to a phase-locked circuit and a radio communication device, which include a calibration circuit with a voltage correction function for supplying a voltage-controlled oscillator with an appropriate calibration voltage. Background technique [0002] Now, in RF transceivers, frequency synthesizers may be essential as local oscillators that can achieve high-precision output frequencies. [0003] figure 1 is a diagram showing a typical configuration of an RF transceiver. [0004] figure 2 is showing figure 1 A diagram of a typical configuration of a PLL (frequency synthesizer) in . [0005] figure 1 The RF transceiver 1 has an antenna 2, a low noise amplifier (LNA) 3, a power amplifier (PA) 4, filters 5 and 6, mixers 7 and 8, and a phase lock circuit (PLL: lock phase ring) 9. [0006] figure 2 The PLL 9 has a phase comparator (phase frequency detector: PFD) 10 , a charge pump (CP) 11 , and a loop filter (LF) 12 . ...

AI Technical Summary

Problems solved by technology

[0059] It is very important that the wrong frequency band is not selected in this frequency calibration

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