CN108806658B - Blood analyzer and buzzer volume adjustment driving circuit thereof - Google Patents
Blood analyzer and buzzer volume adjustment driving circuit thereof Download PDFInfo
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- CN108806658B CN108806658B CN201710317230.4A CN201710317230A CN108806658B CN 108806658 B CN108806658 B CN 108806658B CN 201710317230 A CN201710317230 A CN 201710317230A CN 108806658 B CN108806658 B CN 108806658B
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- 210000004369 blood Anatomy 0.000 title claims abstract description 15
- 239000008280 blood Substances 0.000 title claims abstract description 15
- 239000003990 capacitor Substances 0.000 claims description 17
- 238000004159 blood analysis Methods 0.000 claims 1
- 230000005611 electricity Effects 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 7
- 230000001276 controlling effect Effects 0.000 abstract 2
- 230000001105 regulatory effect Effects 0.000 abstract 2
- 210000000601 blood cell Anatomy 0.000 description 10
- 230000008859 change Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
Classifications
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K9/00—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
- G10K9/12—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Multimedia (AREA)
- External Artificial Organs (AREA)
- Circuit For Audible Band Transducer (AREA)
Abstract
The invention discloses a blood analyzer and a buzzer volume adjusting driving circuit thereof, which comprises a control unit, a PWM driving unit, a volume adjusting unit and a buzzer, wherein the control unit is in control connection with the PWM driving unit and the volume adjusting unit, and the PWM driving unit and the volume adjusting unit are electrically connected with the buzzer; the control unit outputs two groups of control signals: the control signals are used for controlling the PWM driving unit, and when the control signals are in a high level or a low level, the PWM driving unit outputs PWM waveforms to drive the buzzer to sound; the other group of control signals are used for controlling the volume adjusting unit, when the volume of the buzzer needs to be adjusted, the volume adjusting unit outputs signals with different intensities, and the buzzer sends out the volumes with different intensities according to the intensity of the signals output by the volume adjusting unit. The invention can save cost, has simple and reliable circuit, can be regulated at any time according to actual environment, and has simple and effective regulating method.
Description
Technical Field
The invention relates to a blood analyzer, in particular to a blood analyzer and a buzzer volume adjusting driving circuit thereof.
Background
The accurate test products, in particular to a blood cell analyzer of medical clinical test equipment, have very strong dependence of the detection result on the state of the instrument, and the state of the instrument needs to be monitored. Therefore, a buzzer needs to be added, and when the instrument state is abnormal, a user is timely reminded to check the instrument state to remove the fault. Because the inspection type equipment, particularly the blood cell analyzer, is used in a hospital inspection department, when the blood cell analyzer fails, a doctor is not beside the blood cell analyzer, and the sound of the buzzer is enough to remind the doctor; when the blood cell analyzer fails, a doctor just operates the instrument beside the blood cell analyzer, and the sound of the buzzer is required to be small enough to remind the doctor. In addition, when the hospital clinical laboratory equipment is more and the environment is noisy, the sound of the buzzer is required to be loud enough; when the hospital clinical laboratory environment is quiet (e.g., night shifts), the buzzer sound is required to be sufficiently small. Therefore, doctors need to adjust the volume of the buzzer according to different environments so as to meet the use requirements in different environments.
Above the current blood cell analysis, most of the blood cell analysis adopts an active buzzer, and the device is characterized in that a driving circuit is simple, the device can work by applying a voltage, and the device has the defects of constant volume and incapability of adjusting. The volume of the buzzer is adjustable, and only a passive buzzer can be adopted. Currently, a passive buzzer on the market needs to be driven by a control device outputting PWM waves with a certain frequency.
The prior art comprises the following steps: chinese patent CN 104916277A, a passive magneto-electric buzzer driving circuit with adjustable volume and a method thereof, invents a driving method with adjustable volume for passive buzzer. The patent mainly relies on the PWM port of the MCU device to drive the buzzer, and other IO control ports of the MCU are utilized to change the driving current of the buzzer, so that the volume of the buzzer is adjusted.
In summary, certain limitations of the prior art specifically include:
(1) The volume of the buzzer is realized through driving current, and the change of the driving current is realized through changing the current limiting resistor of the driving circuit, so that the size of the current limiting resistor needs to be set in advance, after the current limiting resistor is set, the volume of the buzzer is preset, and a user cannot adjust the volume of the buzzer according to the actual experimental environment because the number of preset volume levels is limited;
(2) The volume adjusting units need to occupy PWM control pins and IO control pins of the MCU device, occupy interface resources of the MCU, and are not beneficial to circuit expansion;
(3) The magnitude of the volume adjustment is preset in advance, and the volume level is not continuous but jumps.
Accordingly, the prior art is still in need of improvement and development.
Disclosure of Invention
The invention aims to provide a blood analyzer and a buzzer volume adjusting and driving circuit thereof, and aims to solve the problem that the buzzer volume of the existing blood analyzer cannot automatically adjust proper volume along with the environment.
The technical scheme of the invention is as follows:
the buzzer volume adjusting driving circuit of the blood analyzer comprises a control unit, a PWM driving unit, a volume adjusting unit and a buzzer, wherein the control unit is in control connection with the PWM driving unit and the volume adjusting unit, and the PWM driving unit and the volume adjusting unit are electrically connected with the buzzer; the control unit outputs two groups of control signals: the control signals are used for controlling the PWM driving unit, and when the control signals are in a high level or a low level, the PWM driving unit outputs PWM waveforms to drive the buzzer to sound; the other group of control signals are used for controlling the volume adjusting unit, when the volume of the buzzer needs to be adjusted, the volume adjusting unit outputs signals with different intensities, and the buzzer sends out the volumes with different intensities according to the intensity of the signals output by the volume adjusting unit.
The buzzer volume adjusting driving circuit of the blood analyzer, wherein the PWM driving unit is an RC multivibrator circuit formed by triodes or a generating circuit, a device or a device capable of generating PWM waveforms.
The buzzer volume adjusting driving circuit of the blood analyzer, wherein the buzzer volume adjusting driving circuit is a digital potentiometer controlled by software or a volume adjusting switch or knob.
The buzzer volume adjustment driving circuit of the blood analyzer, wherein the PWM driving unit circuit structure is as follows: the device comprises a first triode and a second triode, wherein the emitter of the first triode is connected with the emitter of the second triode and grounded; the collector of the first triode is connected with a power supply through a first resistor; the base electrode of the first triode is connected with a power supply through a third resistor; collector of the second triode the power supply is connected through a fourth resistor; the base electrode of the second triode is connected with a power supply through a second resistor; a first capacitor is arranged between the collector of the first triode and the base of the second triode; a second capacitor is arranged between the collector of the second triode and the base electrode of the first triode; the base of the second triode is connected with the control unit through a fifth resistor, and the collector output of the second triode is connected with the buzzer circuit.
The output end of the PWM driving unit is connected with the base electrode of a third triode in the buzzer circuit, the emitter electrode of the third triode is connected with the digital potentiometer, and the collector electrode of the third triode is connected with the buzzer.
A blood analyzer in which the buzzer volume adjustment driving circuit as described above is provided.
The invention has the beneficial effects that: the invention provides a method for realizing a buzzer driving circuit with adjustable volume and application of the buzzer driving circuit in blood cell analysis. Compared with the prior art, the invention has the following advantages:
(1) The PWM driving of the buzzer is generated by a single PWM driving unit, and the unit is an RC multivibrator circuit formed by triodes, so that the circuit is simple and reliable, and the cost is low; without the need for control the PWM interface of the device is provided, resources of the control device may be released;
(2) The PWM driving unit of the buzzer only needs to slightly adjust the resistance parameter, so that the passive buzzers with different specifications can be realized, and the application range is wide;
(3) The volume adjusting unit is a device capable of changing the current of the buzzer in real time, the unit can continuously change the volume of the buzzer, the volume adjusting unit does not need to be preset, the volume adjusting unit can be adjusted at any time according to the actual environment, and the adjusting method is simple and effective.
Drawings
Fig. 1 is a schematic block diagram of a driving circuit provided by the present invention.
Fig. 2 is a circuit diagram of an embodiment of a driving circuit provided by the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clear and clear, the present invention will be further described in detail below with reference to the accompanying drawings and examples.
The driving circuit of the volume adjusting buzzer comprises two parts, wherein one part is a PWM driving unit, and the other part is a volume adjusting unit. The PWM driving unit of the passive buzzer can be provided by an RC multivibrator circuit formed by triodes, and the circuit is simple in design, low in cost and good in stability. The implementation of the volume adjusting unit comprises two modes, wherein one mode is to adjust the volume of the buzzer by matching software with hardware, and the other mode is to adjust the volume of the buzzer by using independent hardware.
As shown in fig. 1, the buzzer volume adjustment driving circuit provided by the present invention includes a control unit 101, a pwm driving unit 201, a volume adjustment unit 301, and a buzzer 401. The control unit is in control connection with the PWM driving unit 201 and the volume adjusting unit 301, and the PWM driving unit 201 and the volume adjusting unit 301 are electrically connected with the buzzer 401.
The control unit 101 outputs two sets of control signals, wherein one set of control signals is used for controlling the PWM driving unit 201, and when the control signal is at a high level or a low level, the PWM driving unit 201 outputs a PWM waveform for driving the buzzer 401 to sound; the other group of control signals are used for controlling the volume adjusting unit 301, when the volume of the buzzer needs to be adjusted, the volume adjusting unit 301 outputs signals with different intensities, and the buzzer 401 sends out volumes with different intensities according to the intensity of the signals output by the volume adjusting unit 301, so that the volume control of the buzzer 401 is realized.
The control unit 101 is a control device, and the control device with an IO interface such as MCU is selected and used in the invention, and one of the functions is to realize the on-off control of the PWM driving unit 201 by outputting a control signal; the second function is to receive the setting signal of the software and transmit the corresponding signal to the volume adjusting unit 301, so as to adjust the intensity of the output signal of the volume adjusting unit 301, thereby realizing the volume adjustment of the buzzer 401.
The PWM driving unit 201 is an RC multivibrator circuit formed by triode or other PWM waveform generation circuit a device or apparatus.
The volume adjustment unit 301 is a digital potentiometer, analog switch, slide rheostat or other resistance changing device or means that acts as a slide rheostat that is set by an MCU or other control device.
The mode of adjusting the volume of the buzzer is software setting or volume adjusting switch or knob or other adjusting modes.
Referring to fig. 2, the present invention provides an embodiment, in which the PWM driving unit 201 is an RC multivibrator circuit formed of a triode. The principle of starting oscillation of the PWM driving unit circuit is that the triode is alternately conducted through charging and discharging of a resistor and a capacitor.
The circuit structure of the PWM driving unit 201 is as follows: the transistor comprises a first triode Q1 and a second triode Q2, wherein the emitter of the first triode Q1 is connected with the emitter of the second triode Q2 and grounded; the collector of the first triode Q1 is connected with a power supply VCC through a first resistor R1; the base electrode of the first triode Q1 is connected with a power supply VCC through a third resistor R3; the collector of the second triode Q2 is connected with a power supply VCC through a fourth resistor R4; the base electrode of the second triode Q2 is connected with a power supply VCC through a second resistor R2; a first capacitor C1 is arranged between the collector of the first triode and the base of the second triode; a second capacitor C2 is arranged between the collector of the second triode and the base of the first triode; the base of the second triode is connected with the control unit through a fifth resistor R, the collector of the second triode, namely the output end of the PWM driving unit, is connected with a buzzer circuit, specifically, the base of a third triode Q in the buzzer circuit is connected, the emitter of the third triode Q is connected with a digital potentiometer, and the collector of the third triode Q is connected with the buzzer.
First, when the circuit is powered on, the first capacitor C1 is charged through the first resistor R1, and the second capacitor C2 is charged through the fourth resistor R4. Because the parameters of the first triode Q1 and the second triode Q2 are not completely consistent, it can be assumed that the first triode Q1 is saturated and conducted first, and the base electrode of the second triode Q2 becomes negative pressure at the moment and the second triode Q2 is cut off because the voltage at two ends of the capacitor cannot be suddenly changed, and the PWM driving circuit outputs high level; the first capacitor C1 is charged through the second resistor R2, when the BE electrode is positively biased by the potential of the second capacitor C2, the second triode Q2 is conducted, and the PWM driving circuit outputs a low level; similarly, the voltages at two ends of the second capacitor C2 cannot be suddenly changed, the base voltage of the first triode Q1 becomes negative voltage, and at this time, the first triode Q1 is turned off. Thus, the PWM driving circuit outputs a square wave signal with a certain frequency, so as to realize the driving of the passive buzzer 401. The output signal frequency of the PWM driving circuit is controlled by the charge and discharge speeds of the second resistor R2 and the first capacitor C1, and the third resistor R3 and the second capacitor C2. The collector of the second triode Q2 is used as the output of the signal, the charging time T1 of the second resistor R2 and the first capacitor C1 determines the high level time of the output signal, and the charging time T2 of the third resistor R3 and the second capacitor C2 determines the low level time of the output signal. And the frequency of the signal is: f=1/(t1+t2). As for the values of the first resistor R1 and the fourth resistor R4, only the rising edge and the falling edge of the PWM signal are affected, and the selection of the resistance is not strictly required.
The volume adjusting unit 301 is a digital potentiometer or a sliding rheostat, when the software inputs parameters for adjusting the volume of the buzzer 401, the control unit 101 changes the control signal of the digital potentiometer, and the digital potentiometer outputs different parameters, so that the buzzer 401 sounds.
According to the software and hardware volume adjustment method, the volume of the buzzer can be adjusted immediately after the adjustment, and the volume can be continuously changed from large to small or from small to large by providing one software operation interface on the operation interface of the blood cell analyzer.
The other volume adjusting method provided by the embodiment of the invention is to adjust the volume of the buzzer in a hardware mode, and a user is required to adjust the volume control switch of the buzzer, so that the volume can be continuously changed from large to small or from small to large.
It is to be understood that the invention is not limited in its application to the examples described above, but is capable of modification and variation in light of the above teachings by those skilled in the art, and that all such modifications and variations are intended to be included within the scope of the appended claims.
Claims (3)
1. The utility model provides a buzzer volume adjustment drive circuit of blood analysis appearance, its characterized in that includes control unit, PWM drive unit, volume adjustment unit and buzzer, control unit control connects PWM drive unit and volume adjustment unit, the buzzer is connected to PWM drive unit and volume adjustment unit electricity, the regulation buzzer volume is software-controlled digital potentiometer or volume adjustment switch or knob, PWM drive unit circuit structure is: the circuit comprises a first triode and a second triode, wherein an emitter of the first triode is connected with an emitter of the second triode and is grounded; the collector electrode of the first triode is connected with a power supply through a first resistor; the base electrode of the first triode is connected with a power supply through a third resistor; the collector electrode of the second triode is connected with a power supply through a fourth resistor; the base electrode of the second triode is connected with a power supply through a second resistor; a first capacitor is arranged between the collector electrode of the first triode and the base electrode of the second triode; a second capacitor is arranged between the collector electrode of the second triode and the base electrode of the first triode; the base of the second triode is connected with the control unit through a fifth resistor, and the collector output of the second triode is connected with the buzzer circuit.
2. The buzzer volume adjustment driving circuit of a blood analyzer of claim 1, wherein the output end of the PWM driving unit is connected to the base of a third triode in the buzzer circuit, the emitter of the third triode is connected to the digital potentiometer, and the collector of the third triode is connected to the buzzer.
3. A blood analyzer, characterized in that the buzzer volume adjustment driving circuit of any one of claims 1 to 2 is provided in the blood analyzer.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710317230.4A CN108806658B (en) | 2017-05-03 | 2017-05-03 | Blood analyzer and buzzer volume adjustment driving circuit thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710317230.4A CN108806658B (en) | 2017-05-03 | 2017-05-03 | Blood analyzer and buzzer volume adjustment driving circuit thereof |
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| CN108806658A CN108806658A (en) | 2018-11-13 |
| CN108806658B true CN108806658B (en) | 2024-04-16 |
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| CN109545178B (en) * | 2019-01-30 | 2023-04-14 | 中科芯集成电路有限公司 | Dual-control buzzer driving circuit |
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2017
- 2017-05-03 CN CN201710317230.4A patent/CN108806658B/en active Active
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