CN208255281U

CN208255281U - The amplification Acquisition Circuit of weak electric signal

Info

Publication number: CN208255281U
Application number: CN201820552848.9U
Authority: CN
Inventors: 王峰
Original assignee: Shandong Huapin Intelligent Engineering Co Ltd
Current assignee: Shandong Huapin Intelligent Engineering Co Ltd
Priority date: 2018-04-18
Filing date: 2018-04-18
Publication date: 2018-12-18
Anticipated expiration: 2028-04-18

Abstract

The amplification Acquisition Circuit of weak electric signal, it is characterised in that: including preamplifying circuit, high-pass filter, rear class amplifying circuit, the input terminal of the output end connection high-pass filter of preamplifying circuit, the output end of high-pass filter connects rear class amplifying circuit.The utility model uses front and back second level to amplify, and common-mode rejection ratio is increased, and has wider frequency band, and noise coefficient is smaller.By intermediate high frequency filter, interference can be weakened, reduce baseline drift degree.The case where post-amplifier can effectively avoid amplifier from being saturated and be distorted.The utility model can accurately reflect the case where acquisition signal, improve the amplified quality of weak electric signal.

Description

The amplification Acquisition Circuit of weak electric signal

Technical field

The utility model belongs to light current field, the amplification Acquisition Circuit of specifically a kind of weak electric signal.

Background technique

In heart and brain weak electric signal treatment process, signal is more faint, and belongs to low frequency signal, can generally carry out to signal Amplification, conventional amplifying circuit is amplified using three-level at present, and the circuit is complex, and three-stage amplifier connection is complicated, is being put It is easy to be disturbed during big, it is ineffective after causing weak electric signal to amplify.

Utility model content

The utility model provides a kind of amplification Acquisition Circuit of weak electric signal, to solve defect in the prior art.

The utility model is achieved by the following technical programs:

The amplification Acquisition Circuit of weak electric signal, it is characterised in that: put including preamplifying circuit, high-pass filter, rear class Big circuit, the input terminal of the output end connection high-pass filter of preamplifying circuit, the output end of high-pass filter connect rear class Amplifying circuit；The preamplifying circuit includes A/D converter C1, between the interface P1 and interface P8 of A/D converter C1 Series resistor R1 and resistance R2, parallel resistance R3 between resistance R1 and resistance R2 are equipped with tracking end between resistance R1 and resistance R2 Mouth XT1；Interface P2, the interface P3 of A/D converter C1 is separately connected input port XT2, input port XT3；A/D converter C1's Interface P4 connection V_DD, the interface P5 connection ground wire of A/D converter C1, the interface P6 of A/D converter C1 is as preamplifying circuit Output end connection high-pass filter input terminal；The interface P7 connection V of A/D converter C1_CC；The high-pass filter packet Include A/D converter C3, serial capacitance C1 and capacitor between the interface P1 of A/D converter C3 and the interface P6 of preamplifying circuit C2, between capacitor C1 and capacitor C2 between the interface P3 of A/D converter C3 series resistor R4, capacitor C2 and A/D converter C3 Resistance R5, the resistance R6 of the interface P2 connection ground terminal of A/D converter C3 of ground terminal are connected between interface P1, A/D converter C3's Connection radio-frequency resistance Rf between interface P2 and resistance R6 between the interface P3 of A/D converter C3, the interface of A/D converter C3 Input terminal of the P3 as high-pass filter output end connection rear class amplifying circuit；The rear class amplifying circuit includes A/D conversion It is gone here and there between the interface P3 of the A/D converter C3 of the interface P1 and high-pass filter of device C2 and A/D converter C3, A/D converter C2 Capacitor C3 is met, is grounded between the interface P1 and capacitor C3 of A/D converter C2 by resistance R7；The interface P2 of A/D converter C2 is logical Cross resistance R8 ground connection, series resistor R9 and adjustable resistance between the interface P3 of the interface P2 and A/D converter C2 of A/D converter C2 Series resistor R11 and electronics R12, resistance R11 between the interface P1 of the interface P3 and A/D converter C3 of R10, A/D converter C2 Serial capacitance C4, the interface P1 of A/D converter C3 pass through capacitor between the interface P3 of A/D converter C3 between electronics R12 C5 ground connection, is connected between capacitor C5 and the interface P2 of A/D converter C3 by resistance R13, resistance R13 and A/D converter C3's It is connect between the interface P3 of A/D converter C3 by resistance R4 between interface P2, the interface P3 of A/D converter C3 is put for rear class The output end of big circuit.

The amplification Acquisition Circuit of weak electric signal as described above, the A/D converter C1 model of the preamplifying circuit For AD620AN.

The amplification Acquisition Circuit of weak electric signal as described above, A/D converter C2, A/D of the rear class amplifying circuit Converter C3 model AD9248.

The amplification Acquisition Circuit of weak electric signal as described above, the model of the A/D converter C3 of the high-pass filter For AD9251.

The utility model has the advantages that: the utility model uses front and back second level to amplify, and common-mode rejection ratio is increased, and is had Wider frequency band, noise coefficient are smaller.By intermediate high frequency filter, interference can be weakened, reduce baseline drift degree.Afterwards The case where grade amplifier can effectively avoid amplifier from being saturated and be distorted.The utility model can accurately reflect acquisition signal The case where, improve the amplified quality of weak electric signal.

Detailed description of the invention

In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is Some embodiments of the utility model, for those of ordinary skill in the art, in the premise of not making the creative labor property Under, it is also possible to obtain other drawings based on these drawings.

Fig. 1 is the structural block diagram of the utility model；The circuit diagram of Fig. 2 preamplifying circuit；Fig. 3 is the electricity of high-pass filter Lu Tu；Fig. 4 is the circuit diagram of rear class amplifying circuit.

Specific embodiment

It is practical new below in conjunction with this to keep the objectives, technical solutions, and advantages of the embodiments of the present invention clearer Attached drawing in type embodiment, the technical scheme in the utility model embodiment is clearly and completely described, it is clear that is retouched The embodiment stated is the utility model a part of the embodiment, instead of all the embodiments.Based on the implementation in the utility model Example, every other embodiment obtained by those of ordinary skill in the art without making creative efforts belong to The range of the utility model protection.

The amplification Acquisition Circuit of weak electric signal, as shown in Figure 1, including preamplifying circuit, high-pass filter, rear class amplification Circuit, the input terminal of the output end connection high-pass filter of preamplifying circuit, the output end connection rear class of high-pass filter are put Big circuit.

As shown in Fig. 2, the preamplifying circuit includes A/D converter C1, the interface P1 of A/D converter C1 and connect Series resistor R1 and resistance R2 between mouth P8, parallel resistance R3 between resistance R1 and resistance R2 are set between resistance R1 and resistance R2 There is trace port XT1；Interface P2, the interface P3 of A/D converter C1 is separately connected input port XT2, input port XT3；A/D turns The interface P4 connection V of parallel operation C1_DD, the interface P5 connection ground wire of A/D converter C1, the interface P6 of A/D converter C1 is as prime The input terminal of the output end connection high-pass filter of amplifying circuit；The interface P7 connection V of A/D converter C1_CC.Preamplifying circuit A/D converter C1 model AD620AN.

As shown in figure 3, the high-pass filter includes A/D converter C3, interface P1 and the prime of A/D converter C3 is put Serial capacitance C1 and capacitor C2 between the interface P6 of big circuit, between capacitor C1 and capacitor C2 with the interface P3 of A/D converter C3 Between series resistor R4, between capacitor C2 and A/D converter C3 interface P1 connect ground terminal resistance R5, A/D converter C3's connects The resistance R6 of mouth P2 connection ground terminal, between the interface P2 and resistance R6 of A/D converter C3 between the interface P3 of A/D converter C3 Connection radio-frequency resistance Rf, A/D converter C3 interface P3 as high-pass filter output end connection rear class amplifying circuit it is defeated Enter end.A/D converter C2, the A/D converter C3 model AD9248 of rear class amplifying circuit.As shown in figure 4, the rear class Amplifying circuit includes A/D converter C2 and A/D converter C3, the A/D conversion of the interface P1 and high-pass filter of A/D converter C2 It is grounded between the interface P1 and capacitor C3 of serial capacitance C3 between the interface P3 of device C3, A/D converter C2 by resistance R7；A/D The interface P2 of converter C2 is grounded by resistance R8, is gone here and there between the interface P3 of the interface P2 and A/D converter C2 of A/D converter C2 Series resistor R11 between the interface P1 of the interface P3 and A/D converter C3 of connecting resistance R9 and adjustable resistance R10, A/D converter C2 With electronics R12, between resistance R11 and electronics R12 between the interface P3 of A/D converter C3 serial capacitance C4, A/D converter C3 Interface P1 be grounded by capacitor C5, connected between the interface P2 of capacitor C5 and A/D converter C3 by resistance R13, resistance R13 It is connect between the interface P3 of A/D converter C3 by resistance R4 between the interface P2 of A/D converter C3, A/D converter C3 Interface P3 be rear class amplifying circuit output end.The model AD9251 of the A/D converter C3 of high-pass filter.

Finally, it should be noted that above embodiments are only to illustrate the technical solution of the utility model, rather than its limitations； Although the utility model is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or part of technical characteristic is carried out etc. With replacement；And these are modified or replaceed, various embodiments of the utility model technology that it does not separate the essence of the corresponding technical solution The spirit and scope of scheme.

Claims

1. the amplification Acquisition Circuit of weak electric signal, it is characterised in that: including preamplifying circuit, high-pass filter, rear class amplification Circuit, the input terminal of the output end connection high-pass filter of preamplifying circuit, the output end connection rear class of high-pass filter are put Big circuit；The preamplifying circuit includes A/D converter C1, is gone here and there between the interface P1 and interface P8 of A/D converter C1 Connecting resistance R1 and resistance R2, parallel resistance R3 between resistance R1 and resistance R2 are equipped with trace port between resistance R1 and resistance R2 XT1；Interface P2, the interface P3 of A/D converter C1 is separately connected input port XT2, input port XT3；A/D converter C1's connects Mouth P4 connection V_DD, the interface P5 connection ground wire of A/D converter C1, the interface P6 of A/D converter C1 is as preamplifying circuit The input terminal of output end connection high-pass filter；The interface P7 connection V of A/D converter C1_CC；The high-pass filter includes Serial capacitance C1 and capacitor C2 between the interface P1 of A/D converter C3, A/D converter C3 and the interface P6 of preamplifying circuit, Between capacitor C1 and capacitor C2 between the interface P3 of A/D converter C3 series resistor R4, capacitor C2 and A/D converter C3 interface The resistance R5 of ground terminal, the resistance R6 of the interface P2 connection ground terminal of A/D converter C3, the interface of A/D converter C3 are connected between P1 The interface P3 of connection radio-frequency resistance Rf, A/D converter C3 between P2 and resistance R6 between the interface P3 of A/D converter C3 make The input terminal of rear class amplifying circuit is connected for high-pass filter output end；The rear class amplifying circuit includes A/D converter C2 With A/D converter C3, electricity is concatenated between the interface P3 of the A/D converter C3 of the interface P1 and high-pass filter of A/D converter C2 Hold C3, is grounded between the interface P1 and capacitor C3 of A/D converter C2 by resistance R7；The interface P2 of A/D converter C2 passes through electricity It hinders R8 to be grounded, series resistor R9 and adjustable resistance R10 between the interface P3 of the interface P2 and A/D converter C2 of A/D converter C2, Series resistor R11 and electronics R12, resistance R11 and electricity between the interface P1 of the interface P3 and A/D converter C3 of A/D converter C2 Serial capacitance C4, the interface P1 of A/D converter C3 are connect by capacitor C5 between the interface P3 of A/D converter C3 between sub- R12 It is connected between the interface P2 of ground, capacitor C5 and A/D converter C3 by resistance R13, the interface of resistance R13 and A/D converter C3 It is connect between the interface P3 of A/D converter C3 by resistance R4 between P2, the interface P3 of A/D converter C3 is rear class amplification electricity The output end on road.

2. the amplification Acquisition Circuit of weak electric signal according to claim 1, it is characterised in that: the preamplifying circuit A/D converter C1 model AD620AN.

3. the amplification Acquisition Circuit of weak electric signal according to claim 1, it is characterised in that: the rear class amplifying circuit A/D converter C2, A/D converter C3 model AD9248.

4. the amplification Acquisition Circuit of weak electric signal according to claim 1, it is characterised in that: the high-pass filter The model AD9251 of A/D converter C3.