Digital audio output control circuit of high-frequency surgical equipment

Abstract

The utility model discloses a digital audio output control circuit of high-frequency surgical equipment, which comprises a host CPU (central processing unit) main control board, a low-pass filter, an audio power amplification circuit, a loudspeaker and two operation keys respectively connected with the host CPU main control board. The output end of the PWM function module of the host CPU main control board is connected with the input end of the low-pass filter, the output end of the low-pass filter is connected with the input end of the audio power amplification circuit, and the output end of the audio power amplification circuit is connected with the loudspeaker. The circuit is simple, audio and volume control is accurate and reliable, and the standard requirement of high-frequency surgical equipment for audio output can be well met.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of medical instruments, especially relates to a digital audio output control circuit of high frequency operation equipment. BACKGROUND

[0002] High frequency operation equipment can produce high frequency current and act on human tissue through electric knife, so that tissue cells are rapidly coagulated, gasified or carbonized, thereby achieving the purpose of hemostasis, cutting and removing tissue, compared with traditional mechanical operation equipment, high frequency operation equipment has better cutting effect and smaller bleeding amount, and is simple and quick to operate.According to the basic safety and basic performance special requirements of high frequency operation equipment and high frequency accessories: high frequency operation equipment must be equipped with an indicator, which provides an audible (sound prompt) signal when any output circuit is excited due to the operation of a single fault state or a single fault state; the main energy of the sound output should be contained in the frequency band of 100Hz~3kHz.According to the above requirements, all high frequency operation equipment must have audio output function, and the frequency and sound intensity of the output audio need to be controlled in the above range.When the high frequency operation equipment is activated, according to different activation states, the host will output audio signals of different frequencies in the operation process according to different activation modes, and emit sound of certain intensity through the loudspeaker equipped in the host, which has obvious prompting effect on the operator.In addition to the alarm prompt sound with fixed volume, the prompt sound of other audio outputs allows users to adjust the size of the output volume.

[0003] At present, various types of high frequency operation equipment with the above multi-audio prompt function on the market generally use analog audio control method to generate the required audio signals of different output frequencies, and the main control CPU also needs to use multiple IO port lines to realize the output control of different audio and volume, and some products also use external potentiometers to realize the volume adjustment function, but the cost is high, the control is relatively complex, and the use effect is not ideal. SUMMARY

[0004] In order to solve the above problems, the purpose of the utility model is to provide a digital audio output control circuit of high frequency operation equipment, which only needs a CPU on the host control board to provide an IO port line with PWM output function for driving control, so as to realize the functions of audio output of different frequencies and volume adjustment.

[0005] In order to achieve the above invention purpose, the utility model adopts the following technical scheme:

[0006] The utility model provides a kind of digital audio output control circuit of high frequency surgical equipment, including host CPU main control board, low pass filter, audio power amplifier circuit, speaker, two operation buttons, the two operation buttons are connected with the host CPU main control board respectively, the output of PWM function module of host CPU main control board is connected with the input of low pass filter, the output of low pass filter is connected with the input of audio power amplifier circuit, the output of audio power amplifier circuit is connected speaker;The low pass filter includes double channel operational amplifier IC2, the output of PWM function module of host CPU main control board IC1 is connected with the same phase input of operational amplifier IC2A by resistance R6, resistance R7, the same phase input of operational amplifier IC2A is connected with negative power supply end and ground by capacitor C6, and the opposite phase input is connected with output by resistance R2, and ground by resistance R4, and positive power supply end is connected with power supply VCC;The output of operational amplifier IC2A is connected with the same phase input of operational amplifier IC2B, and the opposite phase input of operational amplifier IC2B is connected with output and is connected with the connecting point of resistance R6 and resistance R7 by capacitor C5;The audio power amplifier circuit includes audio power amplifier IC3, and the INP end of audio power amplifier IC3 is connected with the output of operational amplifier IC2A by resistance R5, and INN end is connected with GND end and ground by capacitor C2 and resistance R8, and INP end is connected with GND end and ground by capacitor C4, and BYPS end is grounded by capacitor C1, and CTRL end is connected with power supply VCC by resistance R1, VDD end, and there is the resistance R3 and capacitor C3 in series between VOP end and VON end, and VOP end and VON end are connected with speaker Y1.

[0007] Due to the adoption of the technical scheme as described above, the utility model has the following advantages:

[0008] The digital audio output control circuit of high frequency surgical equipment adopts PWM audio modulation technology, and only one IO control line is needed to realize all audio control output functions; the circuit is simple, audio and volume control are accurate and reliable, and the standard demand of high frequency surgical equipment for audio output can be better matched; sine wave signal is used to drive audio power amplification, the audio signal output is round and smooth, the hearing acceptance is good, and the problem of high frequency harsh sound when directly using PWM pulse square wave driving is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 It is the schematic diagram of the digital audio output control circuit of high frequency surgical equipment of the utility model. DETAILED DESCRIPTION

[0010] The technical scheme of the utility model will be further explained in detail by the drawings and embodiments.

[0011] As Figure 1As shown, the digital audio output control circuit of the high-frequency surgical apparatus includes a host CPU main control board, a low-pass filter, an audio power amplification circuit, a speaker Y1, an operation button S1, and an operation button S2. The operation button S1 and the operation button S2 are located on a high-frequency electrotome operation handle, and are respectively connected with the host CPU main control board IC1. The output end of the PWM function module of the host CPU main control board IC1 is connected with the input end of the low-pass filter. The output end of the low-pass filter is connected with the input end of the audio power amplification circuit. The output end of the audio power amplification circuit is connected with the speaker. The low-pass filter includes a dual-channel operational amplifier IC2. The output end of the PWM function module of the host CPU main control board IC1 is connected with the non-inverting input end of the operational amplifier IC2A through resistors R6 and R7. The non-inverting input end of the operational amplifier IC2A is connected with the negative power supply end and grounded through a capacitor C6. The inverting input end is connected with the output end through a resistor R2, and is grounded through a resistor R4. The positive power supply end is connected with a power supply VCC. The output end of the operational amplifier IC2A is connected with the non-inverting input end of the operational amplifier IC2B. The inverting input end of the operational amplifier IC2B is connected with the output end, and is connected with the connection point of the resistor R6 and the resistor R7 through a capacitor C5. The audio power amplification circuit includes an audio power amplifier IC3. The INP end of the audio power amplifier IC3 is connected with the output end of the operational amplifier IC2A through a resistor R5. The INN end is connected with the GND end and grounded through a capacitor C2 and a resistor R8. The INP end is connected with the GND end and grounded through a capacitor C4. The BYPS end is grounded through a capacitor C1. The CTRL end is connected with the power supply VCC through a resistor R1 and a VDD end. The VOP end and the VON end are connected with the speaker Y1 through a resistor R3 and a capacitor C3 in series.

[0012] The functions of the pins of the audio power amplifier IC3 are as follows: the INP end is an audio positive input end; the INN end is an audio negative input end; the BYPS end is a reference voltage end; the CTRL end is a control end; the VOP end is an audio output positive end; the VON end is an audio output negative end; the VDD end is a power supply end; and the GND end is a grounding end.

[0013] Preferably, the chip model of the dual-channel operational amplifier IC2 is LM358, and the chip model of the audio power amplifier IC3 is NS4158.

[0014] The utility model discloses a digital audio output control circuit of high frequency operation equipment's working principle: after the host CPU main control board receives the operation button signal, according to different operation mode, produce a group of PWM rectangular wave that matches with the operation mode working frequency, and send to the second order low pass filter and carry out signal processing, first convert PWM modulation rectangular wave into the triangular wave of same frequency, then convert the triangular wave through RC filter into the sinusoidal wave audio signal of adjustable amplitude, finally send the sinusoidal wave audio signal into audio power amplifier circuit, drive loudspeaker to send the prompt and alarm sound of different frequency.

[0015] In the digital audio output control circuit of high frequency operation equipment of the utility model, set " blood coagulation operation " output prompt sound as fixed frequency 500Hz, set " cutting operation " output prompt sound as fixed frequency 1000Hz.

[0016] Combine Figure 1 , detailed description the working principle of digital audio output control circuit of high frequency operation equipment of the utility model.

[0017] Operation button S1 is used to start " cutting " operation, and operation button S2 is used to start " blood coagulation " operation, when any button in operation button S1, operation button S2 is pressed, the host CPU main control board receives switch signal, and according to different operation mode, automatically produce a output frequency for 400HZ ~ 1200Hz and adjustable duty ratio pulse square wave signal, specifically: when operation button S1 is pressed, and the system activates " cutting " operation, PWM output frequency configuration is low frequency 1000Hz square wave signal, when operation button S2 is pressed, and the system activates " blood coagulation " operation, PWM output frequency configuration is high frequency 500Hz square wave signal.

[0018] The square wave signal generated by the host CPU main control board is output to the dual-channel operational amplifier IC2 for audio conversion processing, and the pulse square wave is converted into a standard sinusoidal wave audio signal, the duty ratio of the PWM output signal is adjusted by the host CPU main control board, the duty ratio variable square wave pulse signal can be converted into a sinusoidal wave audio signal with adjustable amplitude, and by adjusting the amplitude of the audio signal, the audio output volume can be controlled between 0dB and 70dB, and the volume can be linearly adjusted.

[0019] The audio signal with frequency setting and volume adjustment control is output to the audio power amplifier IC3, and the corresponding prompt sound of " cutting ", " blood coagulation " and " alarm " is output by the loudspeaker Y1 according to different operation modes.

[0020] The volume adjusting function realized: the PWM duty cycle of setting the maximum output volume is 50%, with the duty cycle continuously being adjusted lower, the audio power amplifier IC3 output volume is also synchronously reduced, and finally the volume can be completely closed. By adjusting the duty cycle of the PWM signal, the audio signal output amplitude can be normally adjusted, and after the volume adjustment is completed, the PWM volume adjusting parameter can be saved to the host memory, and the configured audio parameter can be directly called every time the machine is started, without the need to repeatedly modify the parameter, which is convenient for users to directly call.

[0021] The above merely describes the preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A digital audio output control circuit for a high frequency surgical apparatus, characterized by: It include host CPU main board, low pass filter, audio power amplifier circuit, speaker, two operation button, two operation button respectively with the host CPU main board is connected, the output of PWM function module of host CPU main board is connected with the input of low pass filter, the output of low pass filter is connected with the input of audio power amplifier circuit, the output of audio power amplifier circuit is connected speaker;The low pass filter includes two channel operational amplifier IC2, the output of PWM function module of host CPU main board IC1 is connected with the same phase input of operational amplifier IC2A through resistance R6, resistance R7, the same phase input of operational amplifier IC2A is connected with negative power supply end through capacitor C6 and ground, the opposite phase input is connected with output through resistance R2, and is grounded through resistance R4, and positive power supply end is connected with power supply VCC;The output of operational amplifier IC2A is connected with the same phase input of operational amplifier IC2B, the opposite phase input of operational amplifier IC2B is connected with output and is connected with the connecting point of resistance R6 and resistance R7 through capacitor C5;The audio power amplifier circuit includes audio power amplifier IC3, the INP end of audio power amplifier IC3 is connected with the output of operational amplifier IC2A through resistance R5, the INN end is connected with GND end through capacitor C2 and resistance R8, the INP end is connected with GND end through capacitor C4, the BYPS end is grounded through capacitor C1, the CTRL end is connected with power supply VCC through resistance R1, VDD end, the resistance R3 and capacitor C3 that have been connected in series between VOP end, VON end, and VOP end, VON end are connected with speaker Y1.

Images