antknee
New Member
I have the following set up: Audio amp --> audio transformer --> piezo
I'm trying to understand just how much power I need. The amp has a big gain bandwidth and i get a decent signal for the frequencies I need ~100KHz. With the mains power this is what I get:
Input into amp 1Vpp @100KHz : output of amp 10Vpp : input into transformer primary 3.2 ohms, 10Vpp : output of transformer 1.2Kohms, 180Vpp : Piezo 180Vpp impedance 100 ohms.
Now: Power =(V x V)/R
So if I do the sums (90 x 90)/100 =80 Watts.
Its that bit I don't get, I clearly don't have 80W on the piezo. So there is some impedance matching that I don't quite get. How do I calculate how many watts I really have on the piezo?
Thanks.
I'm trying to understand just how much power I need. The amp has a big gain bandwidth and i get a decent signal for the frequencies I need ~100KHz. With the mains power this is what I get:
Input into amp 1Vpp @100KHz : output of amp 10Vpp : input into transformer primary 3.2 ohms, 10Vpp : output of transformer 1.2Kohms, 180Vpp : Piezo 180Vpp impedance 100 ohms.
Now: Power =(V x V)/R
So if I do the sums (90 x 90)/100 =80 Watts.
Its that bit I don't get, I clearly don't have 80W on the piezo. So there is some impedance matching that I don't quite get. How do I calculate how many watts I really have on the piezo?
Thanks.