CN102945011A

CN102945011A - Cardiac electrophysiological stimulation waveform distribution circuit

Info

Publication number: CN102945011A
Application number: CN2012105218579A
Authority: CN
Inventors: 夏振宏; 谢陆伟
Original assignee: HUANAN MEDICAL ELECTRICAL TECH Co Ltd HENAN
Current assignee: HUANAN MEDICAL ELECTRICAL TECH Co Ltd HENAN
Priority date: 2012-12-07
Filing date: 2012-12-07
Publication date: 2013-02-27

Abstract

The invention discloses a cardiac electrophysiological stimulation waveform distribution circuit which comprises a singlechip, a stimulation signal generation module, a channel selection decoding circuit module and channel switch control modules, wherein the singlechip is respectively connected with the stimulation signal generation module and the channel selection decoding circuit module; the stimulation signal generation module is respectively connected with the two channel switch control modules; and the channel selection decoding circuit module is respectively connected with the two channel switch control modules. By adopting a complex programmable logic device (CPLD)/ field programmable gate array (FPGA) channel selection circuit and an optical metal oxide semiconductor (MOS) circuit, the cardiac electrophysiological stimulation waveform distribution circuit improves the reliability of the circuit, reduces the power consumption of the circuit, realizes circuit modularization and reduces the problem probability.

Description

Cardiac electrophysiology stimulus waveform distributor circuit

Technical field

The present invention relates to medical instruments field, be specifically related to a kind of cardiac electrophysiology stimulus waveform distributor circuit.

Background technology

At present, in the many threat of heart disease to the mankind, quivering in the ventricle chamber is wherein threaten maximum a kind of.Therefore the ventricle chamber mechanism that occurs of quivering is studied, and under quivering situation in the chamber, the mechanism of electric defibrillation is studied, all have considerable meaning.

The main cause that heart can generating chamber quivers is the vulnerable period of heart in cardiac electrical cycle to be subject to certain stimulation.Within vulnerable period, the recovery extent of each several part myocardial excitability is inconsistent.At this moment, if heart is subject to a stimulus signal, then very easily produce Ventricular Tachycardia or quiver in the chamber.The most frequently used electrophysiological stimulation method is program control stimulus method in early stage (PES) at present, namely by stimulating by prior programmed program with programmable stimulator.

The principle of cardiac electrophysiology stimulation instrument is to utilize the accurate electric pulse deburring of one or more groups programme controlled timing to swash heart, and the reaction of record heart.It can check out in further detail than the cardiogram of routine the pathology of conducting system of heart aspect.And, can successfully and effectively eliminate the effect of turning back by the electro photoluminescence that it is provided, everything is so that it can receive the effect that medicine can not be compared for the treatment of reciprocal tachycardia.

In the interventional cardiac procedures treatment, what often use is polygraph at present.Polygraph can monitor simultaneously and reach 128 tunnel physiological signal in the heart.In the process of operation, the doctor may need the electrical stimulation signal that stimulation instrument sends is added to the pathology that checks the conducting system of heart aspect between any two paths of signals of 128 road physiological signals.It is a huge challenge that stimulus signal up to 128 tunnel distributes for the distributor circuit that uses traditional approach.

The implementation method of the distributor circuit of traditional stimulus signal has two kinds:

The one, use traditional digital signal circuit to finish the selection of stimulus signal passage.Traditionally, practicality is relatively simplified in the system of selection of using digital signal circuit to carry out the stimulus signal passage when stimulation channels quantity is fewer.And when number of channels is many, needing the quantity of the digital signal IC of use sharply to increase, the area of wiring board will increase rapidly.The complicacy of circuit also increases rapidly the power consumption that also can increase simultaneously circuit like this, increases unreliability.

The one, use electromagnetic relay to finish the distribution of stimulus signal.Use electromagnetic relay that following shortcoming is arranged.Electromagnetic relay can not be realized the quick break-make of circuit high frequency, and the electromagnetic relay responsiveness is slow, generally needs the time of tens microseconds to make a response.Can produce the noise of " rattling away " in the process that the electromagnetic relay state switches, and might produce electric spark in the process of switching, cause simultaneously the easy oxidation in contact of electromagnetic relay.In this process, also can produce electromagnetic interference (EMI).In addition, electromagnetic relay is shorter serviceable life.

The 2nd, use multiway analog switch.Multiway analog switch is to switch to select needed analog input signal circuit from a plurality of analog input signals.Multiway analog switch is that field-effect transistors is widely applied as on-off circuit.Its advantage is that operating rate is fast, and conducting resistance is low, and off-resistances is high.The potential safety hazard of using multiway analog switch mainly to exist in stimulation circuit is that multiway analog switch self is with power supply, if device failure will cause the direct current direct effect to cause malpractice to human heart.

As seen, owing to existing above-mentioned defective on the prior art, need a kind of novel circuit to finish the many disadvantages that stimulus signal divides timing to exist.

Summary of the invention

In view of this, the object of the present invention is to provide a kind of cardiac electrophysiology stimulus waveform distributor circuit, adopt CPLD/FPGA channel selection circuit and light MOS circuit, the reliability of intensifier circuit, reduce the power consumption of circuit, realize circuit modular, reduce the probability that goes wrong.

The present invention is by the following technical solutions:

A kind of cardiac electrophysiology stimulus waveform distributor circuit wherein, comprises single-chip microcomputer, stimulus signal generation module, channel selecting decoding circuit module and channel switch control module; Described single-chip microcomputer connects respectively stimulus signal generation module and channel selecting decoding circuit module, the stimulus signal generation module respectively with two channel switch control modules, channel selecting decoding circuit module is connected respectively on two channel switch control modules.

As preferably, described channel selecting decoding circuit module is the CPLD/FPGA channel selection circuit.

As preferably, described channel switch control module is light MOS circuit.

The invention has the beneficial effects as follows:

The digit chip that the CPLD/FPGA channel selection circuit has been abandoned traditional use 74 series such as grade is finished the method for channel selecting, then Programmable Logic Device is finished decoding; Use the method helps to reduce the quantity of the chip that uses in the circuit decoding, the reliability of intensifier circuit, and the power consumption of minimizing circuit realizes circuit modular, the probability that minimizing goes wrong.Simultaneously, if demand has change in the future, the designer can change at any time code and realize, has accelerated the progress of work.

Simultaneously, because light MOS chip as the output channel control circuit of stimulus signal, has been avoided all shortcomings of above-mentioned employing electromagnetic relay, all shortcomings of analog switch have also been avoided using.Simultaneously, also dwindled the volume of circuit board, for contribution has been made in the miniaturization of equipment.

Description of drawings

Fig. 1 is topological structure block diagram of the present invention;

Fig. 2 is the structured flowchart of CPLD/FPGA circuit of the present invention;

Fig. 3 is passage control structure block diagram of the present invention.

Embodiment

The invention will be further described below in conjunction with accompanying drawing and example:

As shown in Figure 1, the present invention includes single-chip microcomputer, stimulus signal generation module, channel selecting decoding circuit module and channel switch control module; Single-chip microcomputer connects respectively stimulus signal generation module and channel selecting decoding circuit module, the stimulus signal generation module respectively with two channel switch control modules, channel selecting decoding circuit module is connected respectively on two channel switch control modules.Channel selecting decoding circuit module is the CPLD/FPGA channel selection circuit.

The power supply that whole circuit uses is to finish and the isolation of network source and the isolation of other circuit parts of polygraph through the DCDC isolation module, to guarantee that patient leakage current satisfies the requirement of safety standard, the needed instruction of single-chip microcomputer work is issued by polygraph, finishes isolation with polygraph by digital isolating chip.Power supply after the isolation changes to respectively about 5V and 3.3V through the LDO module, satisfies the demand of 5V single-chip microcomputer and 3.3V CPLD/FPGA chip operation.

According to the instruction of outside, single-chip microcomputer produces suitable sheet choosing and address signal and outputs to the CPLD/FPGA chip.CPLD/FPGA receives after the instruction that comes from single-chip microcomputer, deciphers, and exports correct channel selecting signal.Selected passage is carried out the instruction of switch, and the stimulus signal of the compound gauge provisioning request that the stimulus signal generation module is produced outputs to human heart, finishes the electrophysiological stimulation function to heart.

As shown in Figure 2, be the functional structure chart of a typical CPLD/FPGA.CPLD/FPGA receives the control signal (CS and ALE) that comes from single-chip microcomputer, and sequential flow process is according to the rules decoded to the signal that receives, and exports the level signal of corresponding P and N.When P and N were selected, corresponding passage is output as chose level, does not choose level otherwise be output as.When the CS signal when not choosing, output channel all is selected state not.

As shown in Figure 3, be light metal-oxide-semiconductor circuit among the present invention.We can find out from figure, and when the signal level of P_CH when being low level, the passage between pin 7 and the pin 8 is in conducting state, and stimulus signal positive output is to the STIMU signal wire.When the signal level of N_CH when being low level, the passage between pin 5 and the pin 6 is in conducting state, and the stimulus signal negative output is to the STIMU signal wire.This is the situation of the control signal work in a-road-through road.If there is any two paths to choose different stimulus signals in the multiplexer channel, then just be applied in stimulus signal between the cardiac muscle between this two paths.By selecting different passages, the medical worker can with stimulus signal switching between the two paths arbitrarily, finish the stimulatory function between the heart any two points.

Need to prove in addition the structure of light metal-oxide-semiconductor.Because the input and output of light metal-oxide-semiconductor partly exist tall and big several kilovolts isolation voltage, like this, even the output terminal of stimulation circuit is subject to defibrillation voltage or electrostatic potential etc. and causes damage, the voltage 3.3V of the work of light metal-oxide-semiconductor can directly not be applied on the human body by output yet.Compare and use the scheme of analog switch, this scheme has improved the safety coefficient of stimulation instrument greatly.

Explanation is at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, other modifications that those of ordinary skills make technical scheme of the present invention or be equal to replacement, only otherwise break away from the spirit and scope of technical solution of the present invention, all should be encompassed in the middle of the claim scope of the present invention.

Claims

1. a cardiac electrophysiology stimulus waveform distributor circuit is characterized in that: comprise single-chip microcomputer, stimulus signal generation module, channel selecting decoding circuit module and channel switch control module; Described single-chip microcomputer connects respectively stimulus signal generation module and channel selecting decoding circuit module, the stimulus signal generation module respectively with two channel switch control modules, channel selecting decoding circuit module is connected respectively on two channel switch control modules.

2. a kind of cardiac electrophysiology stimulus waveform distributor circuit according to claim 1, it is characterized in that: described channel selecting decoding circuit module is the CPLD/FPGA channel selection circuit.

3. a kind of cardiac electrophysiology stimulus waveform distributor circuit according to claim 2, it is characterized in that: described channel switch control module is light MOS circuit.