Piezo transducer/disc and some LEDs

[Taejin]

I need a couple piezo discs and LEDs in short order, but I can't seem to find out where to buy any of this locally.

I live in Montgomery County in Maryland. Can anyone point me to a store where I can go and buy these parts?

Also, how do I know if a piezoelectric transducer generates enough voltage/current (I'm a total scrub at electricity.. don't remember any of my basics) to light up an LED?


Thanks ATOT.

 

[d4mo]

RadioShack?

goldmineelectronics.com is excellent for online.

 

[Taejin]

How do I know whether a piezoelectric transducer I have has the capacity to light up a certain LED? (ie a 3mm vs 5mm vs 10mm LED etc..)

 

[RU482]

http://www.digikey.com/

 

[Fenixgoon]

would mcmaster have this sort of stuff?

 

[DanFungus]

See what kind of voltage/current the transducer can generate, and also look at the voltage/current the LED requires. The 5mm LEDs I have a turn on voltage around 2.0V and take around 25mA of current, but this varies for LEDs particularly between different colors.

Use Ohm's law (V=IR; Voltage (in Volts) = Current (in Amps) * Resistance (in Ohms)) and you should be able to figure it out. Also google "LED calculator" which will help you if you get stuck.

 

[dullard]

I haven't worked much with piezoelectric devices, and that was over a decade ago when I was young. But, I believe most of them are in the 2 mA range (although that will vary by model). LEDs need usually 10mA to just barely see light (although, that will vary by model). Without an amplifier or unusual equipment, I don't see it working.

LEDs can be found at any electronics store locally. Radioshack will have many. Piezoelectric devices are different. About the best you'll likely find is a buzzer or speaker. Then, you'll just use it in reverse. Instead of sending it a signal to make pressure changes (noise), you use pressure changes to make an electric signal. Of course, these are likely optimized for the wrong conditions.

Are you trying to make a piezeoelectric button or switch?