In a typical piezo (noise maker) transducer, will a series R knock
down the amplitude?

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Jim Thompson wrote:

In a typical piezo (noise maker) transducer, will a series R knock
down the amplitude?

Probably not, since they're basically capacitive.

Maybe a cotton ball?

Good Luck!
Rich

"Jim Thompson" schreef
in bericht ...
In a typical piezo (noise maker) transducer, will a series R knock
down the amplitude?

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Suppose so, when it's driven by some voltage source anyway. The energy
dissipated by the resistor will not be transduced into noise.

petrus bitbyter

petrus bitbyter wrote:
"Jim schreef
in bericht ...
In a typical piezo (noise maker) transducer, will a series R knock
down the amplitude?

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Suppose so, when it's driven by some voltage source anyway. The energy
dissipated by the resistor will not be transduced into noise.

petrus bitbyter


It couldn't generate any sound unless its input impedance has a
resisitive component--it would violate conservation of energy. (And
even a pure capacitor would see a decrease in voltage swing if a series
resistance were added.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058

email: hobbs (atsign) electrooptical (period) net
http://electrooptical.net

"Jim Thompson" wrote in
message ...
In a typical piezo (noise maker) transducer, will a series R knock
down the amplitude?

If you're talking about the 2-terminal (externally excited) transducer,
They're largely capacitive and putting a series R will make a low pass
filter. The voltage across the piezo is proportional to the displacement.
This should give a high frequency roll-off according to the RC value.

I've been working with piezo actuators that work in the 0-100V range.
Capacitance is somewhere like 10uF on each piezo.

Oppie

"Phil Hobbs" wrote in message
...
It couldn't generate any sound unless its input impedance has a resisitive
component--it would violate conservation of energy. (And even a pure
capacitor would see a decrease in voltage swing if a series resistance
were added.)

This is a good source of information on piezo actuators/transducers
http://www.physikinstrumente.com/en/...o_tutorial.php

Jim Thompson wrote:
In a typical piezo (noise maker) transducer, will a series R knock
down the amplitude?

...Jim Thompson

Yes. But you may not get the attenuation range you need. (I'm
assuming by "noise maker" you are referring to the kind that have
the oscillator built in, not the kind that are driven by an
external oscillator.) The series R limits the current which
reduces the volume, but it also might stop the internal circuitry
from oscillating due to Vdrop. If you mean the other type where the
oscillator is external, you can shunt attenuate with a parallel cap,
or use a capacitor divider.

Ed