Hi I'm working on a energy harvesting circuit, and i want to harvest from Face Piezeo TH-7R using harvesting chip LTC3588.

The problem is, my input voltage from the piezo is about 150Vp-p and the chip states it will only take in Vin max at 18V.

I have connected some caps in parallel to step down the input to around 20p-p, but it seems to give me very minimal power at 3.3V, which cant even power a tiny LED.

I suspect that it has got to do with the caps.

Any suggestions to step it down by other means? Is resistor possible?

datsheet: 7R http://216.71.30.251/Face International/7r-ds.pdf

datasheet: LTC3588 http://www.linear.com/docs/28909

 

Why do you think that capacitors in parallel will reduce the input voltage? Only a transformer can do that as far as I know. BTW I'm confused, what is it you think the device is doing? Do you think it is converting mechanical energy to electrical energy? The AC voltage that they are talking about is an "applied voltage". I don't think you can bend the device and get an AC voltage out, but like I said I don't understand the purpose of the device and I'm not sure you do either.