Capacitor charge protection circuit for external defibrillator and external defibrillator

Abstract

The embodiment of the invention discloses a capacitor charge protection circuit for an external defibrillator and the external defibrillator. The capacitor charge protection circuit comprises a control circuit power supply, a transformer, a rectifier, a capacitor to be charged, a switch, a switch control steady-state trigger unit, a signal drive unit and a microcontroller. The control circuit power supply is connected with one side of a primary coil of the transformer; the other side of the primary coil of the transformer is connected with the first end of the switch; the second end of the switch is grounded, and the third end of the switch is connected with a switch drive signal; one end of a secondary coil of the transformer is connected with the first input end of the rectifier, and the other end of the secondary coil of the transformer is connected with the second input end of the rectifier; the output end of the rectifier is connected with the capacitor to be charged; the output end of the signal drive unit is connected with the third end of the switch, and the input end of the signal drive unit is connected with the output end of the switch control steady-state trigger unit; the output end of the microcontroller is connected with the input end of the switch control steady-state trigger unit. By means of the capacitor charge protection circuit, the working reliability of the external defibrillator can be improved.

Description

technical field [0001] The invention relates to medical equipment technology, in particular to a capacitor charging protection circuit for an external defibrillator and the external defibrillator. Background technique [0002] Sudden cardiac death (SCD, Sudden Cardiac Death) is the main cause of death of cardiovascular diseases, accounting for more than 50% of the total number of deaths from cardiovascular diseases. Most of the causes of SCD are temporary dysfunction and electrophysiological changes on the basis of various cardiovascular diseases, and cause malignant ventricular arrhythmias, such as ventricular tachycardia (VT, Ventricular Tachycardia, referred to as ventricular tachycardia) And ventricular fibrillation (VF, Ventricular Fibrillation, referred to as ventricular fibrillation) and so on. Studies have shown that once ventricular fibrillation occurs, the success rate of defibrillation will decrease by 10% for every minute of delay. After 10 minutes of ventricula...

AI Technical Summary

Problems solved by technology

[0013] The switch driving signal output by the RC oscillator is a fixed pulse width signal. The pulse width signal has two level states, namely high level state and low level state. The final stable state of the RC oscillator is high level. Therefore, in The stable state of the RC oscillator outputs a high-level pulse width signal to keep the switch on; while the switch drive signal output by the microcontroller is a PWM signal, and the on-off time of the switch is controlled by the PWM signal, but when the microprocessor When the power is turned on, the pin may have a continuous high level, which will also keep the switch in the on state.

[0014] Since the external defibrillator is used as a first-aid equipment, it needs to be able to implement emergency electric shock defibrillation at any time in an emergency state. Therefore, the capacitor to be charged needs to be charged within the shortest possible time (<10ms), that is, within the on-time of the switch. To the high voltage above 1000V, and in the high-speed charging, the switch that is turned on has a large current passing through it, and when the microprocessor or the RC oscillator is not working normally, for example, in the reset state or fault state, the output switch drive signal will affect The conduction time of the switch, if the switch driving signal is not properly controlled, the switch conduction time will be prolonged, thereby burning the switch, making the external defibrillator unusable, and reducing the working reliability of the external defibrillator; The current passing through the switch will saturate the primary coil of the transformer, thus wasting charging energy and reducing charging efficiency

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