CN201402282Y - Signal source for impedance meter - Google Patents

Signal source for impedance meter Download PDF

Info

Publication number
CN201402282Y
CN201402282Y CN200920036815XU CN200920036815U CN201402282Y CN 201402282 Y CN201402282 Y CN 201402282Y CN 200920036815X U CN200920036815X U CN 200920036815XU CN 200920036815 U CN200920036815 U CN 200920036815U CN 201402282 Y CN201402282 Y CN 201402282Y
Authority
CN
China
Prior art keywords
phase
chip
output
locked loop
voltage controlled
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN200920036815XU
Other languages
Chinese (zh)
Inventor
高远
齐本胜
殷明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hohai University Changzhou Campus
Original Assignee
Hohai University Changzhou Campus
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hohai University Changzhou Campus filed Critical Hohai University Changzhou Campus
Priority to CN200920036815XU priority Critical patent/CN201402282Y/en
Application granted granted Critical
Publication of CN201402282Y publication Critical patent/CN201402282Y/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Abstract

The utility model relates to a signal source for an impedance meter. The output end of an active power source is connected with a reference crystal oscillator input end of a phase locked-loop chip through an RC filter circuit; a loop filter is connected at a charge pump output end and a voltage control oscillator input end of the phase locked-loop chip; the voltage control oscillator output A endof the phase locked-loop chip is connected with a cable connector through a capacitor C10; an inductor L3 is connected between the voltage control oscillator output A end and a voltage control oscillator power source end; a capacitor C11 and a resistor R3 are connected in series between the voltage control oscillator output B end of the phase locked-loop chip and the ground; an inductor L4 is connected between the voltage control oscillator output B end and the voltage control oscillator power source end; a resetting end of the phase locked-loop chip is grounded through a resistor R6 and an enabling control end of the phase locked-loop chip is connected with a power source; and four ports of a singlechip are respectively connected with a clock input end, a data input end, a loading enabling end and a multifunction output end of the phase locked-loop chip. The signal source has the advantages that the output signal of the signal source is high in frequency stability, the circuit of thesignal source is simple, and the volume of the impedance meter can be reduced.

Description

The signal source of impedometer
Technical field
The utility model relates to a kind of signal source of impedometer, belongs to the impedometer field.
Background technology
Impedance is the important parameter of expression electronic circuit, element and material, and impedance measuring Instrument is being brought into play very important effect as electronic applications the most basic a kind of measurement means in the every field of electronics industry.Advanced at present impedance measuring Instrument mainly partly is made of signal source, diode electrically bridge circuit and control etc., reaches high-performance, wide-range and high-precision characteristics.But source current signal is made up of crystal oscillator, programmable frequency divider, power amplifier etc., exists the circuit structure complexity, the problem that volume is bigger.
Summary of the invention
The purpose of this utility model provides a kind of output signal frequency precision height, and circuit structure is simple, can reduce the signal source of the impedometer of measuring instrument volume.
The utility model is that the technical scheme that achieves the above object is: a kind of signal source of impedometer comprises single-chip microcomputer, phase-locked loop chip, active crystal oscillator, loop low pass filter and cable splice.The output terminal of described active crystal oscillator connects the reference crystal oscillator input end of phase-locked loop chip through the RC filtering circuit, the charge pump output terminal of phase-locked loop chip and voltage controlled oscillator input end T-Ring path filter, the voltage controlled oscillator output A end of phase-locked loop chip connects cable splice through capacitor C 10, and inductance L 3 connects between voltage controlled oscillator output A end and the voltage controlled oscillator power end, be connected in series capacitor C 11 and resistance R 3 between the voltage controlled oscillator of phase-locked loop chip output B end and the ground, inductance L 4 connects between voltage controlled oscillator output B end and the voltage controlled oscillator power end, voltage controlled oscillator power supply termination power, the reset terminal of phase-locked loop chip is through resistance R 6 ground connection, enable to control termination power, phase-locked loop chip two tuning coil ends are respectively through inductance L A and LB ground connection, the capacitance compensation end is through capacitor C 13 ground connection, and the decoupling capacitor end connects power supply through capacitor C 15; Four ports of described single-chip microcomputer connect input end of clock, data input pin, load enable end and the multi-functional output terminal of phase-locked loop chip respectively.
Signal source of the present utility model utilizes single-chip microcomputer to have programmable function and collection digital frequency phase detector and programmable charge pump, R frequency divider able to programme, Fractional-N frequency device able to programme, programmable multiple output port and the voltage controlled oscillator phase-locked loop chip for one, can be by the control of simple peripheral circuit and single-chip microcomputer to phase-locked loop chip, the output frequency accurate signal, and reduced the measuring instrument volume.
Description of drawings
Below in conjunction with accompanying drawing embodiment of the present utility model is described in further detail.
Fig. 1 is the electrical schematic diagram of the utility model signal source.
Wherein: 1-single-chip microcomputer, the active crystal oscillator of 2-, 3-RC filtering circuit, 4-phase-locked loop chip, 5-cable splice, 6-loop low pass filter.
Embodiment
See shown in Figure 1ly, the signal source of impedometer of the present utility model comprises single-chip microcomputer 1, phase-locked loop chip 4, active crystal oscillator 2, loop low pass filter 6 and cable splice 5.This single-chip microcomputer adopts AT89 series, and as AT89C2051, phase-locked loop chip 4 adopts the ADF4360 chip series, as ADF4360-8 chip or ADF4360-4 chip etc.The ADF4360-8 chip internal has comprised a low noise digital frequency phase detector, programmable charge pump, R frequency divider able to programme, programmable Fractional-N frequency device and programmable multiple output port and voltage controlled oscillator.See shown in Figure 1,2 pin ground connection of the active crystal oscillator 2 of the utility model, 3 pin connect output, 4 pin connect power supply, the output terminal of active crystal oscillator 2 connects the reference crystal oscillator input end of phase-locked loop chip 4 through RC filtering circuit 3, this RC filtering circuit 3 is made of resistance R 7 and capacitor C 17, C18, and resistance R 7 connects between capacitor C 17, C18 node and the ground.Through active crystal oscillator 2 and RC filtering circuit 3, provide the oscillating reference signal of high stability to phase-locked loop chip 4.The frequency of this input oscillating reference signal is f R, behind 14 R counter frequency divisions of phase-locked loop chip 4 inside, signal frequency becomes f r=f R/ R sends into the digital frequency phase detector and the current pump output of phase-locked loop chip 4 inside again.The charge pump output terminal and the voltage controlled oscillator input end of phase-locked loop chip 4 are connected to loop low pass filter 6, by loop low pass filter 6, can filtering by voltage controlled oscillator output signal and reference signal bit comparison mutually produced corresponding to radio-frequency component in the error voltage of two signal phase differences and noise, to guarantee the desired performance of loop, increase the stability of system.See shown in Figure 1ly, this loop low pass filter 6 is made of resistance R 8, R9 and capacitor C 6, C7, C8, resistance R 9 and capacitor C 7 serial connection branch roads, capacitor C 6 and resistance R 8 and capacitor C 8 serial connection branch roads, and three branch road parallel connections are to form passive 3 rank loop filters.See shown in Figure 1ly, the voltage controlled oscillator of phase-locked loop chip 4 output A end connects cable splice 5 through capacitor C 10, and inductance L 3 connects between voltage controlled oscillator output A end and the voltage controlled oscillator power end, is f by voltage controlled oscillator output terminal output frequency OutSignal.And be connected in series capacitor C 11 and resistance R 3 between the voltage controlled oscillator of phase-locked loop chip 4 output B end and the ground, inductance L 4 be connected on that voltage controlled oscillator output B holds and the voltage controlled oscillator power end between, voltage controlled oscillator power supply termination power.The output signal of voltage controlled oscillator feeds back to 13 Fractional-N frequency devices at chip internal, and signal frequency becomes f behind the Fractional-N frequency device V=f Out/ N.This signal is sent into the digital frequency phase detector of chip internal again, with the input signal f behind the R frequency division rRemake the phase bit comparison, when both same same phase times frequently, promptly loop is in the lock state.The reset terminal R of phase-locked loop chip 4 SetThrough resistance R 6 ground connection, so that maximum charge pump output current to be set.Enable control end CE and connect power supply, promptly external high level is so that the chip operate as normal.Phase-locked loop chip 4 liang of tuning coil ends L1 and L2 are respectively by inductance L A and LB ground connection, and inductance L A and LB be parallel resistance R4 and R5 respectively, by different inductance value, controls the output signal frequency f of voltage controlled oscillator OutSize.The capacitance compensation end Cc of phase-locked loop chip 4 is through capacitor C 13 ground connection, and decoupling capacitor end Cn connects power supply through capacitor C 15.The pin of earth terminal external ground, the pin of power end external power supply.
See shown in Figure 1,1 four ports of the utility model single-chip microcomputer are P1.3, P14, P1.5, the P1.6 end meets the input end of clock CLK of phase-locked loop chip 4 respectively, data input pin DATA, load enable end LE and multi-functional output terminal MUXOUT, for serial data transmission provides clock, and receive the serial data that single-chip microcomputer 1 sends, the load enable end is used for control data and writes relevant register, and multi-functional output terminal can be exported the signal behind the R frequency division, signal behind the Fractional-N frequency, simulation locking indication, sheet internal informations such as number lock indication, accurately output unlike signal frequency is measured complex impedance accurately and effectively.

Claims (2)

1, a kind of signal source of impedometer, it is characterized in that: comprise single-chip microcomputer (1), phase-locked loop chip (4), active crystal oscillator (2), loop low pass filter (6) and cable splice (5), the output terminal of described active crystal oscillator (2) connects the reference crystal oscillator input end of phase-locked loop chip (4) through RC filtering circuit (3), the charge pump output terminal of phase-locked loop chip (4) and voltage controlled oscillator input end are connected to loop filter (6), the voltage controlled oscillator output A end of phase-locked loop chip (4) connects cable splice (5) through capacitor C 10, and inductance L 3 connects between voltage controlled oscillator output A end and the voltage controlled oscillator power end, be connected in series capacitor C 11 and resistance R 3 between the voltage controlled oscillator of phase-locked loop chip (4) output B end and the ground, inductance L 4 connects between voltage controlled oscillator output B end and the voltage controlled oscillator power end, voltage controlled oscillator power supply termination power, the reset terminal of phase-locked loop chip (4) is through resistance R 6 ground connection, enable to control termination power, phase-locked loop chip (4) two tuning coil ends are respectively through inductance L A and LB ground connection, the capacitance compensation end is through capacitor C 13 ground connection, and the decoupling capacitor end connects power supply through capacitor C 15; (1) four port of described single-chip microcomputer connects input end of clock, data input pin, load enable end and the multi-functional output terminal of phase-locked loop chip (4) respectively.
2, the signal source of impedometer according to claim 1 is characterized in that: described phase-locked loop chip (4) adopts the ADF4360 chip.
CN200920036815XU 2009-02-26 2009-02-26 Signal source for impedance meter Expired - Fee Related CN201402282Y (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN200920036815XU CN201402282Y (en) 2009-02-26 2009-02-26 Signal source for impedance meter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN200920036815XU CN201402282Y (en) 2009-02-26 2009-02-26 Signal source for impedance meter

Publications (1)

Publication Number Publication Date
CN201402282Y true CN201402282Y (en) 2010-02-10

Family

ID=41662079

Family Applications (1)

Application Number Title Priority Date Filing Date
CN200920036815XU Expired - Fee Related CN201402282Y (en) 2009-02-26 2009-02-26 Signal source for impedance meter

Country Status (1)

Country Link
CN (1) CN201402282Y (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105827239A (en) * 2016-03-21 2016-08-03 成都天进仪器有限公司 Clock circuit for intelligent relay protection tester
CN110837057A (en) * 2019-11-06 2020-02-25 西安交通大学 Battery impedance spectrum measuring system and measuring method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105827239A (en) * 2016-03-21 2016-08-03 成都天进仪器有限公司 Clock circuit for intelligent relay protection tester
CN110837057A (en) * 2019-11-06 2020-02-25 西安交通大学 Battery impedance spectrum measuring system and measuring method

Similar Documents

Publication Publication Date Title
CN105527501B (en) A kind of micro capacitance method
CN102916679B (en) Circuit and the control method thereof of accurate low-frequency clock signal are provided
CN203590195U (en) Improved simulation integrating circuit based on PCB Rogowski coil current transformer
CN106324048B (en) A kind of soil humidity sensor and its working method based on oscillation circuit
CN201402282Y (en) Signal source for impedance meter
CN108225495A (en) A kind of capacitance level transducer on-line measurement system and its method
CN201413117Y (en) Frequency-modulating variable-area eddy current displacement sensor
CN106501618B (en) Capacitor's capacity measuring circuit
CN204142265U (en) A kind of sensor detection circuit
CN204496001U (en) Laser range finder
CN204258753U (en) A kind of high accuracy clock circuit of resistance to high overload based on thick-film resistor
CN103412194B (en) Capacitance measuring and calculating circuit
CN208432658U (en) A kind of electric energy meter and its AFE(analog front end) meeting IR46 standard
CN205176101U (en) Power frequency high voltage measurement device based on SF6 gas -insulated high voltage standard capacitor
CN2926998Y (en) Anti-interference circuit board of digital flowmeter
CN203377840U (en) Different crystal load matching circuit in crystal oscillator and IC
CN204740293U (en) Capacitive sensor circuit
CN203909178U (en) Multifunctional digital electric power meter
CN201422100Y (en) Crystal oscillating circuit and electronic device with crystal oscillating circuit
CN104316774A (en) Absolute capacitor and differential capacitor measuring circuit
CN203661009U (en) Circuit improving crystal oscillator resonance frequency
CN210742385U (en) Crystal oscillator frequency measuring system
CN102082549A (en) Voltage control crystal oscillator
CN105785202A (en) Dynamic electric energy quality detection apparatus
CN214310702U (en) Detection circuit and device for inductor

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant
C17 Cessation of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20100210

Termination date: 20130226