Unlock instant, AI-driven research and patent intelligence for your innovation.

Charge Pump Phase Locked Loop, Capacitor Multiplication Method and NC Loop Filter

A loop filter, charge pump technology, applied in the direction of electrical components, automatic power control, etc., can solve the problems of capacitance multiplication coefficient PLL damping coefficient can not be accurately controlled, PLL circuit additional noise, increased cost and other problems

Active Publication Date: 2017-11-24
ANALOG DEVICES INT UNLTD
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The second charge pump uses additional IC area and results in increased power dissipation and increased cost
Also, due to the mismatch between the two charge pumps, the capacitance multiplication factor as well as the PLL damping factor cannot be precisely controlled
Also, the second charge pump will cause additional noise in the PLL circuit

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Charge Pump Phase Locked Loop, Capacitor Multiplication Method and NC Loop Filter
  • Charge Pump Phase Locked Loop, Capacitor Multiplication Method and NC Loop Filter
  • Charge Pump Phase Locked Loop, Capacitor Multiplication Method and NC Loop Filter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0021] The present invention provides a system and method for phase locked loop (PLL) capacitance multiplication using a charge pump and digitally controlled loop filter. Embodiments employ digitally controlled loop filters operating in time-division mode. Embodiments of the loop filter block current from the charge pump according to the digital control so that the charge pump cannot charge or discharge the integrating capacitor when the digital control is activated. Therefore, the charge pump will take more time to charge or discharge the capacitor to a certain level. This way, the capacitor appears larger than it actually is.

[0022] For a more detailed understanding of the present invention, reference is now made to figure 1 . figure 1 A block diagram of an exemplary charge pump phase locked loop circuit (PLL) 100 with charge multiplication using one charge pump is shown. PLL 100 includes a phase detector (PD) 102 , a charge pump (CP) 104 , a digitally controlled loop ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A system and method for capacitance multiplication with a charge pump for a phase locked loop employs a digitally controlled loop filter operating in a time division mode. Embodiments of the loop filter block current from the charge pump according to the digital control when the digital control is enabled so that the charge pump cannot charge or discharge the integrating capacitor. Since at least a portion of the current is blocked, the charge pump needs more time to charge or discharge the capacitor to a certain level. Then, relative to the operation of the PLL, the capacitor appears larger than it really is.

Description

technical field [0001] The present invention relates to capacitive multiplication using a digitally configured loop filter for a charge pump phase locked loop (PLL) circuit. Background technique [0002] A Phase Locked Loop or Phase Locked Loop (PLL) is a negative feedback control system in which the signal generated by the oscillator is phase and frequency locked to an input reference signal. Embodiments include an electronic circuit including a phase detector, a charge pump, a filter including integrating capacitor C1 and resistor R1, and a frequency variable oscillator. A phase detector compares the phase of an input reference signal with the phase of a signal derived from the output of the oscillator and generates an error signal. The charge pump converts the error signal into an error current, and the integrating capacitor C1 and resistor R1 act according to the error current to generate the oscillator control voltage. Integrating capacitor C1 integrates the error cur...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H03L7/099
CPCH03L7/0895
Inventor 高亭严杰锋
Owner ANALOG DEVICES INT UNLTD