Piezoelectric Electronic Circuits

Piezoelectric Circuits Page 3
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Last Updated on: Sunday, April 22, 2012 07:19 AM

Circuits Designed by Dave Johnson, P.E. :

Piezoelectric Triggered Switch
Two different switch circuits are shown. One sources current and the second sinks current. Both switches are connected to a piezoelectric wafer. When the wafer is tapped, the switches are activated.

Piezoelectric Vibration Sensor Activates Switch
An inexpensive piezoelectric wafer is used to detect vibration and when the vibration is sufficient a switch is activated. (added 7/06)

Ultra Low Power 32KHz Crystal Oscillator
I have used this circuit many times when I needed a low frequency reference, which did not draw much power. With the components show, the current from a 3v battery is less than 1.2 microamps.

VERY LOUD BEEPER CIRCUIT
This circuit generates a continuous tone instead of a pulsing one. The circuit delivers about 110db (12 inches away) from a 9v battery using a single inexpensive C-MOS IC. An off-the-shelf piezoelectric beeping device is driven at resonance to insure maximum efficiency.

Very Loud Piezoelectric Beeper Circuit
This circuit is similar to circuit number 7, but generates a continuous tone instead of a pulsing one. The circuit delivers about 110db (12 inches away) from a 9v battery using a single inexpensive C-MOS IC. An off-the-shelf piezoelectric beeping device is driven at resonance to insure maximum efficiency.

Very Loud Pulsating Beeper Keeps Average DC Current Draw Low - Many battery powered alarms draw excessive current when operating. Some of the most attention-getting noise makers, such as the unit shown below, use piezoelectric sound generators with a frequency sweeping tone. When operating with a 9v battery, these units can often draw 100ma or more. In many applications, a continuous alarm sound is not needed. Locating a balloon or a rocket are examples where you want a loud sound but a low average power drain. To lower the average current, the device can be pulsed with short 0.05 second chirps, once every two or three seconds. This lowers the average current by a factor of 60. So, instead of drawing 100ma, by chirping the alarm, the current is lowered to just 2ma. The circuit below generates the pulse train needed for these short but very loud chirp sounds.

Links to electronic circuits, electronic schematics, designs for engineers, hobbyists, students & inventors:

Piezo crystal monitors liquid level - 03/30/00 EDN-Design Ideas....The simple and inexpensive circuit in Figure 1 monitors the liquid level in a container. The piezo crystal, carefully mounted at the bottom surface of the container, receives it activation from the 74HCT14 hex Schmitt trigger. The….PDF contains multiple circuits, please scroll to find this one.... [Design Idea by J Jayapandian, IGCAR, Tamil Nadu, India]

Piezo device generates buzz, beep, or chime - 04/23/98 EDN-Design Ideas Piezoelectric buzzers, such as the Murata (Smyrna, GA] PKB5-3A in Figure 1, make excellent alarms. They're compact, lightweight, efficient, and reliable. However, a piezo alarm is a dc device; it requires additional circuitry to operate from an ac source. The circuits in Figure 1 provide a simple and inexpensive way to obtain the dc drive. The W04G full-wave bridge rectifie....File contains several circuits, scroll to this one.... [Design Idea by Dennis Eichenberg, Parma Heights, OH]

Piezo Disk - (electronic schematic / circuit added 2/05)

Piezo Education/Tutorial - PPL stands for 'Phase-Locked Loop' and is basically a closed loop frequency control system, which functioning is based on the phase sensitive detection of phase difference between the input and output signals of the controlled oscillator (CO). You will find no formulas or other complex math within this tutorial. I decided to keep it simple. But, before we go into any detail, first a little bit of history of the Phase-Locked Loop and prior to that with the superheterodyne.…. [written by Tony van Roon]

Piezo Pickup Amplifier Circuit - AS098 Jenson Transformer Application Note (app note 6/07)

Piezo Vibration Sensors - Circuit diagram of the vibration sensing circuit out of a toy dog that barks when he senses a thump nearby… [Reverse engineered schematic by Stepan Novotill]

Piezoelectric driver finds buzzer’s resonant frequency - 7-Aug-08 Issue of EDN By driving a piezoelectric buzzer near its resonant frequency and counting the residual oscillations, a microcontroller can find the buzzer's resonant frequency.... [Design Idea by Mehmet Efe Ozbek, PhD, Atilim University, Incek, Ankara, Turkey]

Piezoelectric Tone Generation Using the MAXQ3210 - Maxim App Note 4148 -- 2/04/2008 -- (app note add 5/08)

Piezoelectric transformer - If there is a need to feed very low power devices you may resort to infrared optocouplers, solar cells, batteries or low power transformers although the latter might be rather oversized for the intended purpose. Eventually, with the exception of solar cells, all....(added 04/08)

Piezoelectric Triggered Switch - Two different switch circuits are shown. One sources current and the second sinks current. Both switches are connected to a piezoelectric wafer. When the wafer is tapped, the switches are activated. (added 7/06) …. [Designed by David A. Johnson]

Piezoelectric Vibration Sensor Activates Switch - An inexpensive piezoelectric wafer is used to detect vibration and when the vibration is sufficient a switch is activated. (added 7/06) …. [Designed by David A. Johnson]

Point-contact oscillators - The principle of operation of a car hooter has been applied to both a ceramic sounder and a loudspeaker. A break in the supply current is caused by the vibration of the ceramic sounder plate or the speaker membrane. You could implement similar circuits even without a transformer but the voltage range will be limited, there....(added 03/09)

Remote Switch uses No Power Fiber Optic Link - 10/10/96 EDN-Design Ideas....The heavy-duty switching device in Figure 1 counts the number of products manufactured and rolled out of a production line per hour. The switch is useful for counting rolling heavy objects or materials weighing one to several thousand kilograms. It generates one pulse per.... EDN is migrating links. This link is not verified. Google the "title" + EDN for new link.

Shock Sensor Circuit Prevents Data Corruption - 07/04/96 EDN-Design Ideas.... Hard-disk drives for laptop and other portable applications need to withstand significant g-force shocks when operating. A typical 1.8-in. drive writes servo information over less than 15% of the disk's active area, which means that the read/write head spends more than 85%.... EDN is migrating links. This link is not verified. Google the "title" EDN for new link.

Ultra Low Power 32kHz Crystal Oscillator - I have used this circuit many times when I needed a low frequency reference, which did not draw much power. With the components show, the current from a 3v battery is less than 1.2 microamps. …. [Designed by David A. Johnson]

Very Loud 3v Powered Beeper - Getting a high sound intensity from a piezoelectric type beeper is not easy when the available DC supply is only 3v. The circuit below is not only efficient but produces a very intense sound. The circuit combines a voltage boost section with a resonant feedback network. The voltage applied to the piezoelectric wafer is about 40 volts peak to peak. The result is a circuit that generates an attention getting sound without drawing a lot of current. [Designed by David A. Johnson]

VERY LOUD BEEPER CIRCUIT - This circuit generates a continuous tone instead of a pulsing one. The circuit delivers about 110db (12 inches away) from a 9v battery using a single inexpensive C-MOS IC. An off-the-shelf piezoelectric beeping device is driven at resonance to insure maximum efficiency. [Designed by David A. Johnson]

Very Loud Piezoelectric Beeper Circuit - This circuit generates a continuous tone instead of a pulsing one for your hobby project. As seen in the schematic, the hobby circuit delivers about 110db (12 inches away) from a 9v to 12v source using a single inexpensive C-MOS IC. …. [Hobby Corner Circuit by Dave Johnson]

Very Loud Pulsating Beeper Keeps Average DC Current Draw Low

White LED shines from piezoelectric oscillator supply - 10-Jan-08 Issue of EDN A piezoelectric ceramic buzzer powers a white LED from a single cell.... [Design Idea by TA Babu, Chennai, India]