You can double or triple the output by using a pea-whistle. Since the Piezo is basically set at one frequency, you can put a tuned pipe on top of the Piezo. I used a large bottle cap to start with and just moved it around until I found the resonant frequency. Then I refined it a bit & made a resonator more mechanically robust. No extra IC amps or driver power
This is the simple solution that I use in some designs although I normally use single XOR gates as they are more general purpose and of course they should still have TTL thresholds at 5V compatible with the Prop so normally the 74HCT family or others (the 74LVC series still requires a minimum 3.75V Vih @5V) . For much louder sounding the RS232 driver solution is cheap and compact as I use a cap array and a tiny TSSOP pack RS232 chip.
The inductor solution is bulky and still not as cheap as the active solution and besides the inductor can't really be driven straight from the Prop pin.
EDIT: Sorry Tony, just noticed that the chip you mentioned is a dual output crystal driver so that's a good solution in place of my dual gates. The confusing thing though is that they spec Vih at the normal 0.8xVcc yet in the features section they say it's TTL compatible.
Why not just use a much louder piezo beeper? It's not hard to find cheap, relatively efficient ones (<10mA) that are extremely loud. (Assuming you need one frequency)
This is the simple solution that I use in some designs although I normally use single XOR gates as they are more general purpose and of course they should still have TTL thresholds at 5V compatible with the Prop so normally the 74HCT family or others (the 74LVC series still requires a minimum 3.75V Vih @5V) . For much louder sounding the RS232 driver solution is cheap and compact as I use a cap array and a tiny TSSOP pack RS232 chip.
The inductor solution is bulky and still not as cheap as the active solution and besides the inductor can't really be driven straight from the Prop pin.
EDIT: Sorry Tony, just noticed that the chip you mentioned is a dual output crystal driver so that's a good solution in place of my dual gates. The confusing thing though is that they spec Vih at the normal 0.8xVcc yet in the features section they say it's TTL compatible.
Peter,
Please forgive me as I am an electronics neophyte, but I need to drive a piezo as loudly as possible. I like the sound of your TSSOP solution, but I have no idea how to implement it. Can you please point me in the direction of where I might find a schematic of this kind of circuit? Thanks mate.
Please forgive me as I am an electronics neophyte, but I need to drive a piezo as loudly as possible. I like the sound of your TSSOP solution, but I have no idea how to implement it. Can you please point me in the direction of where I might find a schematic of this kind of circuit? Thanks mate.
Ah, you just caught me as I was about to retire. Here's a circuit which use a TSSOP chip and a cap array. The 220R is simply a "placeholder" so I introduce resistance to limit the drive but otherwise it's not required. The BUZZ signal is from the Prop and can be generated by the counters very easily.
Comments
http://www.mouser.com/Semiconductors/_/N-5gcbZscv7?Keyword=74LVC1GX04&Ns=Pricing%7c0&FS=True
Pros: only need one mcu pin to get +-25mA push/pull @ 10v pk-pk
This is the simple solution that I use in some designs although I normally use single XOR gates as they are more general purpose and of course they should still have TTL thresholds at 5V compatible with the Prop so normally the 74HCT family or others (the 74LVC series still requires a minimum 3.75V Vih @5V) . For much louder sounding the RS232 driver solution is cheap and compact as I use a cap array and a tiny TSSOP pack RS232 chip.
The inductor solution is bulky and still not as cheap as the active solution and besides the inductor can't really be driven straight from the Prop pin.
EDIT: Sorry Tony, just noticed that the chip you mentioned is a dual output crystal driver so that's a good solution in place of my dual gates. The confusing thing though is that they spec Vih at the normal 0.8xVcc yet in the features section they say it's TTL compatible.
So looking at the cut sheet,
You connect VCC to 5V
Connect your IC square wave output to X1
Connect your piezo accross X2 and Y
This give you a 10v p-p square wave across the piezo?
Peter,
Please forgive me as I am an electronics neophyte, but I need to drive a piezo as loudly as possible. I like the sound of your TSSOP solution, but I have no idea how to implement it. Can you please point me in the direction of where I might find a schematic of this kind of circuit? Thanks mate.
Ah, you just caught me as I was about to retire. Here's a circuit which use a TSSOP chip and a cap array. The 220R is simply a "placeholder" so I introduce resistance to limit the drive but otherwise it's not required. The BUZZ signal is from the Prop and can be generated by the counters very easily.