CN209342752U

CN209342752U - A kind of IEPE excitation and conditioning circuit

Info

Publication number: CN209342752U
Application number: CN201822258928.6U
Authority: CN
Inventors: 贾润利
Original assignee: Shaanxi Onis Electronic Technology Co Ltd
Current assignee: Shaanxi Onis Electronic Technology Co Ltd
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2019-09-03
Anticipated expiration: 2028-12-29

Abstract

The utility model relates to a kind of IEPE excitation and conditioning circuits; including excitation IEPE constant-current source, LC filter module, AC coupled module, overvoltage crowbar and the programmable amplifying circuit being sequentially connected electrically; the overvoltage crowbar is used to carry out JFET overvoltage protection, and the programmable amplifying circuit is used for small and weak vibration signal programming amplifying；The excitation IEPE constant-current source is the 4mA constant-current source stimulus sensor based on PSSI2021SAY；The LC filter module is LC low-pass filtering module.The utility model has the advantages that user-friendly simple single-ended input fashion goes acquisition, analysis, have stability high, signal-to-noise ratio is high, the low advantage of harmonic wave；The programmable amplifying circuit of rear end uses program-controlled amplifier, these integrated resistance precisions are very high, and matching degree is very good, and temperature drift, which can be ignored, not to be remembered, to ensure that the signal-to-noise ratio of Dynamic Signal, harmonic performance and low drifting performance.

Description

A kind of IEPE excitation and conditioning circuit

Technical field

The utility model belongs to driving circuit technical field, and in particular to a kind of IEPE excitation and conditioning circuit.

Background technique

With big aircraft, development need and bridge, the building of destroying the domestic advanced industries such as 20 etc., fight shock levels Requirement it is also higher and higher, but domestic sound, vibration industry be to the confusion in sound, the excitation of vibration class sensor, conditioning, with And the status that conditioning circuit THD index is low, it is provided that

1, the constant current source forcing designed using LM317

The crossing current source forcing mode of the program is feasible, but due to the limitation of LM317 direct plugging member size, does multichannel battle array Can be very difficult when column, integrated level is relatively low；

2, using the conditioning mode of AD620

The instrument amplifier that AD620 is generally used as a industry, occasion of the output for 12 bit AD samples are very excellent Show, but industry generally uses 24 acquisition schemes at present, and the drawback in AD620 performance just exposes undoubtedly.It exports bottom and makes an uproar greatly, The undesirable defect of harmonic performance, the conditioning circuit worked it out with its scheme allow in acquisition very low, the harmonic wave that often faces signal-to-noise ratio The very low problem of performance, and since the amplification of AD620 is to need to be arranged using external resistance, and the performance of external resistance is direct The performance of AD620 output signal is affected, the generally existing external big influence AD620 output of resistance temperature drift has drift；

3, series resistance+clamp diode scheme is used on protection scheme

Although this protection scheme is available, due to the very high common-mode voltage of vibration signal, and due to not having when shock sensor In the case where connecting, very high common-mode voltage (such as 24V or even 30V voltage) is forced into resistance and diode, two Pole pipe fever, and the pressure drop with resistance is also very big, so that resistance itself is generated heat, can drop low-resistance service life in this way, causes reliable Property problem, meanwhile, fever can also cause thermal noise, influence measurement performance.

Existing Chinese patent document CN201410564002 discloses a kind of the general high-precision of IEPE type acceleration transducer Spend signal regulating device IEPE excitation and conditioning circuit, main technical schemes are as follows: a kind of IEPE type acceleration transducer leads to With high-precision signal conditioning device, including constant current source module, signal blocking module, signal inversion module, power module, feature It is, further includes normalization module, filter module, the power module is used for as the general of the IEPE type acceleration transducer The comprising modules of high-precision signal conditioning device provide direct-current working volts, and respectively with constant current source module, signal blocking module, Signal inversion module, normalization module are connected with filter module；The constant current source module is for exporting constant current excitation IEPE The work of type acceleration transducer, and be connected with IEPE type acceleration transducer；The signal blocking module is for adding IEPE type Speed sensor signal carries out DC isolation filtering to generate ac voltage signal, reaches driving of the enhancing circuit to capacitive load Ability, and the stability of holding circuit work, avoid generating self-oscillation phenomenon, and as voltage follower, the signal Blocking module is connected with IEPE type acceleration transducer and normalization module respectively；The normalization module is used for will be different sensitive The sensor of degree output normalizing be same output signal amplitude range, and respectively with signal blocking module and filter module phase Even；The filter module is used to carry out high-pass filtering and low-pass filtering to ac voltage signal, and respectively with normalization module and Signal inversion module is connected；The signal inversion module is used for the ac voltage signal by being inverted in the normalization module Restore sense, and is connected with filter module.It is different from the utility model.

Utility model content

The purpose of this utility model is to solve the above problems, and provides a kind of IEPE excitation and conditioning circuit, has stability Height, signal-to-noise ratio is high, the low advantage of harmonic wave.

To achieve the above object, the utility model provides the following technical solutions:

A kind of IEPE excitation and conditioning circuit, including be sequentially connected electrically excitation IEPE constant-current source, LC filter module, hand over Coupling module, overvoltage crowbar and programmable amplifying circuit are flowed, the overvoltage crowbar is used to carry out overvoltage protection to JFET, The programmable amplifying circuit is used for small and weak vibration signal programming amplifying.

Further, the excitation IEPE constant-current source is the 4mA constant-current source stimulus sensor based on PSSI2021SAY.

Further, the LC filter module is LC low-pass filtering module.

Further, the excitation IEPE constant-current source is 24V.

The utility model has the beneficial effects that:

4mA constant-current source stimulus sensor of the utility model based on PSSI2021SAY, LC low-pass filtering, JFET scheme Overvoltage protection and programming amplifying, ensure that the stability of signal, low bottom make an uproar, low harmonics distortion, low excursion with temperature characteristic, be user Provide conditioned Low ESR, high quality sound/vibration signal.User-friendly simple single-ended input fashion goes to adopt Collection, analysis have stability high, and signal-to-noise ratio is high, the low advantage of harmonic wave；The programmable amplifying circuit of rear end uses program-controlled amplification Device, these integrated resistance precisions are very high, and matching degree is very good, and temperature drift, which can be ignored, not to be remembered, to ensure that Dynamic Signal Signal-to-noise ratio, harmonic performance and low drifting performance.

Detailed description of the invention

In order to illustrate more clearly of the utility model embodiment technical solution, will make below to required in embodiment description Attached drawing is briefly described, it should be apparent that, the accompanying drawings in the following description is only the utility model in order to more clearly Illustrate the utility model embodiment or technical solution in the prior art, for those of ordinary skill in the art, is not paying Out under the premise of creative work, it is also possible to obtain other drawings based on these drawings.

Fig. 1 is that the system of the utility model constitutes block diagram；

Fig. 2 is utility model works flow chart.

Specific embodiment

A kind of IEPE excitation as shown in Figs. 1-2 and conditioning circuit, including be sequentially connected electrically excitation IEPE constant-current source 1, LC filter module 2, AC coupled module 3, overvoltage crowbar 4 and programmable amplifying circuit 5, the overvoltage crowbar 4 are used In carrying out overvoltage protection to JFET, the programmable amplifying circuit 5 is used for small and weak vibration signal programming amplifying.

Further, the excitation IEPE constant-current source 1 is the 4mA constant-current source stimulus sensor based on PSSI2021SAY.

Further, the LC filter module 2 is LC low-pass filtering module.

Further, the excitation IEPE constant-current source 1 is 24V.

Utility model works principle are as follows:

The constant-current source of 4mA is directly accessed analog channel by input terminal, to be directly accessed excitation IEPE constant-current source 1 (IEPE sensor), IEPE sensor generate voltage according to the variation of variation sound or vibration, and voltage is filtered by LC Module 2 enters AC coupled module 3, because IEPE sensor is equivalent to a variable resistance, so, one is superimposed on voltage Fixed common-mode voltage, this common-mode voltage are not actually required signals, filter out this common-mode voltage by AC coupled module 3.By The impact signal very big there may be amplitude when board is in impact, just seems necessary to the protection of rear end, this is practical new Abundant consideration is done to protection part in type, using the protection scheme of JFET, when voltage is higher, JFET can be equivalent to one The variable resistance of a resistance value reduces thermal noise to reduce heating power.The programmable amplifying circuit 5 of rear end uses program-controlled Amplifier because programmable amplifier has been internally integrated the resistor network through laser post-treatment, these integrated resistance precisions are very Height, matching degree is very good, and temperature drift, which can be ignored, not to be remembered.To ensure that the signal-to-noise ratio, harmonic performance and low drift of Dynamic Signal Move performance.

The utility model realizes the functions such as the excitation to sound, shock sensor signal, conditioning, amplification, filtering, has Stability is high, and signal-to-noise ratio is high, the low advantage of harmonic wave.

The content not being described in detail in the utility model is the prior art.

The above is only the preferred embodiment of the utility model only, is not intended to limit the utility model, all at this Within the spirit and principle of utility model, any modification, equivalent replacement, improvement and so on should be included in the utility model Protection scope within.

Claims

1. a kind of IEPE excitation and conditioning circuit, which is characterized in that including be sequentially connected electrically excitation IEPE constant-current source (1), sense Capacitor filter module (2), AC coupled module (3), overvoltage crowbar (4) and programmable amplifying circuit (5), the overvoltage protection electricity Road (4) is used to carry out JFET overvoltage protection, and the programmable amplifying circuit (5) is used for small and weak vibration signal programming amplifying.

2. a kind of IEPE excitation according to claim 1 and conditioning circuit, which is characterized in that the excitation IEPE constant-current source It (1) is the 4mA constant-current source stimulus sensor based on PSSI2021SAY.

3. a kind of IEPE excitation according to claim 1 and conditioning circuit, which is characterized in that the LC filter module It (2) is LC low-pass filtering module.

4. a kind of IEPE excitation according to any one of claims 1 to 3 and conditioning circuit, which is characterized in that the excitation IEPE constant-current source (1) is 24V.