Questions tagged [piezo]
Piezoelectricity is the electric charge that accumulates in certain solid materials (such as crystals, certain ceramics, and biological matter such as bone, DNA and various proteins) in response to applied mechanical stress.
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Purpose of switch in transimpedance amplifier
The schematic below is for a piezoelectric sensor. For the transimpedance op-amp, what is the purpose of the switch (SW1)? To my understanding, when the switch is on the bandwidth is reduced by the ...
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Generate vibration and sense with the same piezo
I would like to build a sensor that generates some vibration on a material and then sense the vibration of the material. The simplest approach seems like using a piezo transducer. Ideally in ...
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41 views
Mimicking the output of a piezo sensor with a membrane potentiometer
High level
I'm trying to use an electronic drum pedal as an electronic drum trigger. My specific e-drum unit has only one pedal input, so I need to repurpose a drum trigger input in order to use more ...
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Can I use Op-Amps to drive a ultrasonic piezo transducer at 200kHz
I’ll admit I’m not the most knowledgeable guy when it comes to electronic circuits, so I thought I’d ask before breaking anything.
I’m looking to drive a piezo transducer using a 200kHz sine wave. The ...
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Adapting a universal preamp to a piezo microphone
for a school project I'm trying to adapt a universal mic preamp to a piezo mic: obviusly with the original circuit i've obtained a low distortion.
The preamp is a Velleman k1803 mono preamp:
I've ...
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75 views
Do almost all modern smartphones use piezoelectric speakers?
Do almost all modern smartphones use piezoelectric speakers for both the ear speaker and the speakerphone speaker?
The reason I ask is because I rinsed off my waterproof smartphone (which I've done ...
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76 views
How to surpress coupling between two circuits
I have the following setup:
2 piezo transducers are placed 0.7 meter apart from eachother in water facing eachother. 1 piezo (PA) acts as the sender, the other piezo (PB) acts as the receiver.
PA ...
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1answer
52 views
Easiest way to (quietly) drive a 2W 120VAC load (piezo air pump) from MCU-controlled 3V/5V/12V?
I'm trying to drive this piezoelectric air pump that requires 1.5W and runs on 120VAC 60Hz wall power.
This will be controlled by a MCU/CPU of some kind (Raspberry Pi in this instance), so the control ...
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CW Doppler probe for fetal doppler and blood flow velocity
I am currently working on a microcontroller based project to measure the blood flow velocity using ultrasound doppler.
I have purchased two Spengler 8 MHz continuous mode probes in order to measure ...
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134 views
Can a MOSFET or transistor be used to switch on a 9V supply using a 3.3V signal?
***Technical question, not a wiring problem.
I am building a bicycle alarm system and I'm a little stuck on the alarm output. I wonder if I am approaching this problem wrong.
My alarm piezo ...
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36 views
Touch sensor selection
I am currently researching a touch/force sensor for my project. Purpose of this post is to get your help in sensor selection.
Below is the information about the project so that you can get insight ...
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Help Designing an Impact Detector for Raspberry Pi
I am trying to design a little game where you throw a baseball at a 3x3 grid of 24x18" polycarbonate panels (1/4" thick), and the game detects which of 9 panels is struck. I'm aware there ...
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59 views
Reducing resonance in a piezoelectric ultrasonic transducer
I am using a piezo transducer to launch an ultrasonic pulse in air, at a frequency of 125kHz. A picture of the received waveform is attached. My question concerns how I can (electronically) limit the ...
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1answer
78 views
What is the use of drain diodes in the circuit below?
This TC7920 driver will be driving a piezo electric load which may behave like a capacitive load at certain frequencies. There is another IC TC8220 which is the same except it is not having the drain ...
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1answer
35 views
What are the advantages and advantages of ceramic and Langevin transducers for ultrasonic cleaners?
I have an old large ultrasonic cleaner with 5 ceramic piezo electric transducers (pictured below) epoxied to its tank's underside. They use around 40W of power each.
Newer ultrasonic cleaners, ...
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28 views
Noise in Voltage Buffer
I am trying to build a voltage buffer for a piezoelectric record player cartridge. The amp built into the record player doesn't provide the necessary impedance. I have tried multiple circuits ...
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1answer
48 views
Amplifier circuit for Bently Nevada velomitor 330525
I'm in need of measuring vibrations and I have access to these Bently Nevada velomitors.
I'm not sure how to design a ampliefier circuit for the signal.
The datasheet is says that it is a piezo ...
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4answers
52 views
LTSpice sweep resistance
I would like to plot the power obtained by this simple recovery circuit (UR1eff^2/R1) according to the value of the resistance R1. But as it is a sinusoidal function, it takes the average value of the ...
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SSHI circuit on LTSpice
I've been trying to get an SSHI circuit running on LTspice for several days now (see below schematic). My problem is the following: the simulation (.tran) stops after a hundred milliseconds. Being a ...
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Piezoelectric coefficient modes 31 and 33 - What's the difference?
I'm having a hard time understanding the difference between model 31 and 33.
I understood it as follows:
These terms are ratio of strain with applied field, whereas the indices represent the direction ...
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43 views
Turning on a latch circuit with a piezo sensor?
I am trying to build a relatively 'simple' circuit with a piezo sensor that turns on an LED for ~10-20 seconds after it has been tapped.
In the off-state the circuit should use zero current to ...
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2answers
163 views
Piezo signal amplifier using LM358 opamp
I was trying to amplify the signal of a piezo, which is very low and amplify it so that I could use it to latch a flipflop. I had the LM358 opamp so I made a differential amplifier by a gain of 50 so ...
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72 views
protect op amp input from overvoltage from piezo sensor
I use a piezo to register the moment of a knock via a micro controller's analog in (1.8V Max)
So far I used the scheme in the figure without any diodes. This works so far, but depending on the knocks ...
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46 views
Piezo cantilever energy harvester: how to mesure such small power?
I am currently designing a piezo energy harvester and I would like to modify the resonating frequency to maximize the energy recovered(for exemple by changing the center of mass of the cantilever). My ...
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415 views
Protecting circuit from piezoelectric disc voltage spike
I have a piezoelectric disc, and I'm trying to use to build a primitive sonar. I connected the disc to an oscilloscope and if I press very hard on the disc, I see that the voltage can spike pretty ...
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136 views
Stick-Slip Piezo Linear Stage Driver - Prevent the Load from Changing Driver Output?
I am currently trying to develop a circuit that generates ramp waveforms to control the motion of a piezo linear stage.
Specifically, two waveforms need to be possible to output: a slow ~250us upward ...
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84 views
Does the type of preamplifier used for a piezoelectric sensor change its physical resonant frequency?
Two common amplifier circuits used for piezoelectric sensors are voltage amplifiers and charge amplifiers (pictured respectively).
With the charge amplifier, the sensor is shorted but this is not the ...
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1answer
276 views
Is this design of a charge amplifier for a piezoelectric sensor correct?
This is the specifications that must be met: "Design a charge amplifier for a piezoelectric sensor that has 500 pF capacitance. It should pass frequencies from 0.05 to 100 Hz so that it can ...
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64 views
Debugging a SA 90.4 800W class-D audio amplifier
I am using a Re-audio SA 90.4 800W 4-channel class D audio amplifier (https://www.amazon.com/REAudio-SA90-4-4-Channel-Digital-Amplifier/dp/B00RE9EO7K) for some underwater piezoacoustics experiment. ...
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2answers
53 views
Why do magnet door/window alarms use always-on switches?
I am looking at door/window alarm designs, and they all use overcomplicated circuits with an always on switch, where the piezo is triggered when the switch is off.
If the switch was always off, it ...
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1answer
135 views
6-channel piezo buffer jfet circuit
Even though I'm a total beginner at electronics, I've decided to build a 6-channel piezo pickup buffer/mixer unit, for a stringed instrument. It should fit into a typically sized electronics cavity, ...
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106 views
How to DRIVE a piezo driver circuit
I want to implement a driver circuit for piezo actuators for a positioning system. For this, I require a high-voltage, low-current output, similar to the one discussed here which features a circuit ...
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37 views
Driving piezo scanner tubes using the driven internal electrode configuration
I'm planning on doing a project involving a piezo tube scanner (PTS). The PTS will be used for 3 axis manipulation of a sharp needle. PiezoDrive has a few scanners and some info on how to use them. ...
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226 views
Protect Op Amp input from piezo sensor overvoltage
I have a circuit that I'm using to detects "knocks" using a piezo element. It seems to work adequately, but as I half suspected, I have now demonstrated that it's possible for the piezo element to ...
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Piezoelectric Backscatter Communication
I am currently working on a project. We have a metal bar as test object and at each end we stuck a piezo disc. I am trying to use one piezo as a sender and the other as receiver or reflector. I tried ...
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73 views
Is it possible to drive a power piezoelectric in lower frequency than its own frequency?
I am driving a piezo transducer simply by an inductor series with piezo.
the resonant frequency of the piezo is about 40KHz and I designed a 20KHz transducer.
I'm giving a pulse voltage (using a class ...
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1answer
167 views
What happens when DC is applied to a piezo crystal?
I've heard that when an alternating current is passed through a piezo crystal it vibrates. But what happens if a direct current is passed through the crystal? I'm assuming depending on the direction ...
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Ultrasonic dual transmitter-receiver circuit
I am building an ultrasonic flow sensor, based on piezoelectric actuators from cheap HR-SR04 modules. I need to measure the speed of sound back and forth. Schematic like this is good to send pulses:
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How can I protect my amplifier, MCU, and laptop from damage in my application circuit?
I am trying to integrate a few devices for a laser stabilization system. I have a tentative circuit diagram that I'm asking for more expert guidance in implementing. I am using an MX200 from ...
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675 views
Help me understand this high voltage amplifier circuit for driving a piezo actuator
I am researching HV driver amplifiers for controlling piezoactuators. My background is in physics, so I am a bit out of my comfort zone here. I came across the following schematic and have been ...
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Convert analog piezo “transition” to digital signal
I'm trying to get what amounts to a knock indication into a microcontroller input from a piezo sensor. It's looking fairly good now at the fifth iteration, and about ready to provide digital levels ...
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3answers
159 views
What should I do to control the impedance in piezoelectric energy harvester
I am trying to design an piezoelectric energy harvester circuit and using voltage multiplier rectifier to build it now.
I am using a piezo film, LDT4-028k as a source and it has 11nF cap inside the ...
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1answer
130 views
Is it possible to combine two CFU455IT +/-2kHz (4kHz) ceramic filters to get a +/-1.25kHz bandwith (2.5kHz) filter?
Can I put two of these cheap (less than 3USD) and common CFU455IT +/-2kHz (4kHz bandwith -6dB ) ceramic filters in series to get a lower bandwidth good for SSB TX? If I'm correct I will get -12dB at +/...
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Sensing of AC current. Isolation Capacitor Problems?
I want to measure the AC Current flowing through a Piezocrystal (replaced in the circuit with a resistor) being driven by a TI DRV2700. http://www.ti.com/lit/ds/symlink/drv2700.pdf
This Chip puts out ...
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171 views
Are ultrasonic Tx/Rx pairs really just the same sensor?
I want to retool the classic HC SR04 rangefinder to be able to do ToF gas flow sensing. I need to be able to do ToF on a column of air in both directions, so it benefits me to be able to use the ...
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MPU 6050 accelerometer generating gaussian noise with strange gaps
I was using an GY-521 accelerometer/gyroscope module in order to provide inertial tracking. The GY-521 interfaces with an Arduino which sends data over a serial connection. I convert these values into ...
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How does this piezo input circuit work?
The following circuit is part of an electronic drum kit, and is repeated several times on the board to connect piezo elements to a micro-controller that samples the various inputs. I've represented ...
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piezo sensor drums
I am sure their is an answer but my question is very basic ( i am a total novice in electrical engineering ) but have a coding/maths background.
I have a simple piezo sensor ( see image .
Question ...
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MOSFET source measures 12V, still nothing will turn on
Please, bear with me, I'm a real rookie at electrical engineering. So please be easy on me. ;-)
I've got the following circuit. I have a 5 seconds HIGH / LOW interval on ...
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2answers
42 views
Break beam sensor to replace piezo transducer
I have a device intended to sound an alarm and flash a bright light when it detects a phone ringing (so you can hear the phone ringing in noisy environments like workshops). I want to repurpose it to ...
