CN202776292U

CN202776292U - Circuit structure of electrocardiosignal acquisition module

Info

Publication number: CN202776292U
Application number: CN 201220477253
Authority: CN
Inventors: 刘宇; 吴�灿; 刘阳
Original assignee: CHANGSHA ALCAN ELECTRONIC Co Ltd
Current assignee: CHANGSHA ALCAN ELECTRONIC Co Ltd
Priority date: 2012-09-19
Filing date: 2012-09-19
Publication date: 2013-03-13
Anticipated expiration: 2022-09-19

Abstract

The utility model discloses a circuit structure of an electrocardiosignal acquisition module. The circuit structure comprises a power supply, a processor, a plurality of radio-frequency filtering and impedance conversion circuits, a plurality of anti-aliasing filtering circuits, a lead shed detection circuit, a right leg driving circuit and a shielding driving circuit. According to the utility model, precise digital amplification is realized by a high-precision AD converter, so that the consistency among channels is good; the hardware scale of an anti-aliasing filter is reduced by virtue of oversampling of the high-precision AD converter; a digital filter implemented by the high-speed processor has the functions of acquiring an excellent filtering effect and reducing the hardware cost instead of an analog filter; and by means of the digital filter and high-precision sampling, the size of the circuit is reduced, the technological requirement on the production is lowered, the capability of resisting severe environments is enhanced, and the hardware circuit scale is reduced as well.

Description

A kind of ecg signal acquiring modular circuit structure

Technical field

This utility model relates to a kind of electrocardiogram signal acquisition device, particularly a kind of ecg signal acquiring modular circuit structure.

Background technology

Along with the progress of digitizing technique with popularize, analog circuit composition in the electronic product that we often use is fewer and feweri, the application of digital technology has brought the advantages such as high-performance, low-power consumption, low price and small size of electronic product, can say that digital technology allows electronic product that revolutionary progress has been arranged.

Electrocardiograph is a kind of electromedical equipment of precision, and it is painted into the faint electrocardiosignal of human body on the drawing, is provided as the foundation of patient diagnosis Xiang the doctor, or as important monitoring foundation.Electrocardiograph is as the product that is widely used, digitizing technique also gets more and more in this product in recent years and is used, but the main aspect of infiltration of digitizing technique is still in aspect functions such as analog digital conversion, demonstration, storage, printings at present, although this this greatly promoted the function of electrocardiograph, analog channel has still been continued to use traditional circuit.

The quality of analog channel is one of place that affects electrocardiograph performance most critical, it also is the part of bringing the shortcomings such as volume is large, cost is high, interference free performance is weak, digitizing technique is the further introducing of circuit in this section, will obtain to a great extent overcoming these defectives.

The introducing of digital filter is providing under the same even more high performance prerequisite, the problem that provides analog filter to solve or needed huge hardware costs to solve.

Summary of the invention

Technical problem to be solved in the utility model is, and is not enough for prior art, and a kind of ecg signal acquiring modular circuit structure is provided, and realizes that accurate numeral amplifies, and improves interchannel concordance, reduces hardware size and cost, reduces the circuit volume.

For solving the problems of the technologies described above, the technical scheme that this utility model adopts is: a kind of ecg signal acquiring modular circuit structure, comprise power supply, processor, some rf filterings and impedance inverter circuit, some Anti-aliasing Filter Circuits, the testing circuit that comes off leads, driven-right-leg circuit, the shield guard circuit, described rf filtering and impedance inverter circuit input are connected with tested human body, described rf filtering and impedance inverter circuit outfan access described Anti-aliasing Filter Circuits input, described Anti-aliasing Filter Circuits outfan is by 24 AD changer access processors, and described processor is by power conversion and filter circuit access power supply; Described driven-right-leg circuit, shield guard circuit, lead come off the testing circuit input and access described rf filtering and impedance inverter circuit outfan and Anti-aliasing Filter Circuits input between, described driven-right-leg circuit outfan accesses tested human body; Described shield guard circuit output end accesses the electrode wires screen layer of described rf filtering and impedance inverter circuit input; The described testing circuit outfan access processor that comes off that leads.

Compared with prior art, the beneficial effect that this utility model has is: this utility model is realized accurate numeral amplification, interchannel high conformity by the high-precision A/D changer; Reduce the hardware size of frequency overlapped-resistable filter by the over-sampling of high-precision A/D changer; The digital filter of realizing by high speed processor substitutes analog filter, and obtains excellent filter effect, has reduced hardware costs; By digital filter and high-precision sampling, reduced the volume of circuit, reduced the technological requirement of producing, strengthened the ability of anti-adverse environment, equally also reduced the scale of hardware circuit.

Description of drawings

Fig. 1 is this utility model one example structure block diagram;

Fig. 2 is this utility model one embodiment rf filtering circuit and impedance inverter circuit schematic diagram;

Fig. 3 is this utility model one embodiment Anti-aliasing Filter Circuits schematic diagram;

Fig. 4 is this utility model one embodiment shield guard circuit theory diagrams;

Fig. 5 is this utility model one embodiment driven-right-leg circuit schematic diagram;

Fig. 6 is this utility model one embodiment power conversion and filter circuit schematic diagram;

Fig. 7 is this utility model one embodiment testing circuit schematic diagram that comes off that leads.

The specific embodiment

As shown in Figure 1, this utility model one embodiment comprises power supply, processor, eight rf filtering circuit and impedance inverter circuit, eight Anti-aliasing Filter Circuits, testing circuit, driven-right-leg circuit, the shield guard circuit of coming off leads, described rf filtering and impedance inverter circuit input are connected with tested human body, described rf filtering and impedance inverter circuit outfan access described Anti-aliasing Filter Circuits input, described Anti-aliasing Filter Circuits outfan is by 24 AD changer access processors, and described processor is by power conversion and filter circuit access power supply; Described driven-right-leg circuit, shield guard circuit, lead come off the testing circuit input and access described rf filtering and impedance inverter circuit outfan and Anti-aliasing Filter Circuits input between, described driven-right-leg circuit outfan accesses tested human body; Described shield guard circuit output end accesses the electrode wires screen layer of described rf filtering and impedance inverter circuit input; The described testing circuit outfan access processor that comes off that leads.

As shown in Figure 2, rf filtering circuit of the present utility model is the RC filter circuit, and impedance transformation adopts operational amplifier to realize; The effect of rf filtering and impedance inverter circuit is the radiofrequency signal of removing on the human body, and the high resistant source impedance of human body is transformed to the low-resistance signal.

As shown in Figure 3, Anti-aliasing Filter Circuits adopts the RC filter circuit, its effect is the spectral aliasing of avoiding in the sampling process, it is-low pass filter of 3dB point about 150Hz, because 24bitAD changer 3 is 2400Hz to the sample frequency of each passage, substantially exceeded 150Hz, so only need simple RC wave filter can finely reach anti-aliasing effect.

As shown in Figure 4, shield guard 7 circuit take out the human body midpoint potential acts on conducting wire after amplifier drives screen layer, further improve the input impedance of this module, also play preventing that external interference from entering the effect of input channel by conducting wire.

As shown in Figure 5, driven-right-leg circuit oppositely amplifies the right lower limb of rear drive human body with the human body midpoint potential, and its effect is to improve CMMR, further suppresses common mode disturbances.

As shown in Figure 6, power conversion and filter circuit adopt the NCP699SN33T1G chip, and its effect provides the required voltage of modular circuit, carry out as required offering the use of various piece circuit after the filtering.

As shown in Figure 7, the testing circuit that comes off of leading detects connection and the pacing signal of conducting wire and human body in real time, and this signal is offered high speed processor, finishes detection and the pacing signal identification of leading and coming off by it.

The effect of 24bitAD changer 3 is that faint ECG signal is converted to the digital signal that 24bit represents, to the switching rate 2400Hz of every passage; Its model is ADS1258.

High speed processor (model: LPC2131) accept the electrocardiogram digital signal that the 24bitAD changer is sent here, it is carried out digital conversion and digital filtering, simultaneously the signal that testing circuit is sent here is responsible for also that reading leads and comes off by high speed processor, detection dropping situations and the pacing signal identification of leading, at last with the module duty, the come off signal, pace-making recognition result of leading form Frame with ECG data, export by the UART mouth on the high speed processor.

Claims

1. ecg signal acquiring modular circuit structure, comprise power supply, processor, some rf filterings and impedance inverter circuit, some Anti-aliasing Filter Circuits, the testing circuit that comes off leads, driven-right-leg circuit, the shield guard circuit, it is characterized in that, described rf filtering and impedance inverter circuit input are connected with tested human body, described rf filtering and impedance inverter circuit outfan access described Anti-aliasing Filter Circuits input, described Anti-aliasing Filter Circuits outfan is by 24 AD changer access processors, and described processor is by power conversion and filter circuit access power supply; Described driven-right-leg circuit, shield guard circuit, lead come off the testing circuit input and access described rf filtering and impedance inverter circuit outfan and Anti-aliasing Filter Circuits input between, described driven-right-leg circuit outfan accesses tested human body; Described shield guard circuit output end accesses the electrode wires screen layer of described rf filtering and impedance inverter circuit input; The described testing circuit outfan access processor that comes off that leads.

2. ecg signal acquiring modular circuit structure according to claim 1 is characterized in that, described Anti-aliasing Filter Circuits is single order RC filter circuit.

3. ecg signal acquiring modular circuit structure according to claim 1 is characterized in that, described power conversion and filter circuit adopt the NCP699SN33T1G chip.

4. ecg signal acquiring modular circuit structure according to claim 1 is characterized in that, described processor model is LPC2131.

5. ecg signal acquiring modular circuit structure according to claim 1 is characterized in that, described 24 AD changer models are ADS1258.

6. ecg signal acquiring modular circuit structure according to claim 1 is characterized in that, described rf filtering and impedance inverter circuit, Anti-aliasing Filter Circuits quantity are 8.