Other Parts Discussed in Thread: DRV2700, , LM48560, LM48580
I am considering TI part DRV8662 to drive a 20nF piezo bender/speaker at 25Vp-p and 4kHz. I know the DRV8662 is targeted for haptic applications (frequencies in 200 to 500Hz range), but I am planning to use it at the lowest gain setting – this gives a bandwidth of 20kHz. Since our piezo control signal is at 4kHz, this should be fine. But I did notice on the DRV8662 product page, there is a recommendation for the DRV2700 for general purpose (non-haptic) applications. Now the DRV2700 has the same 20 pin QFN package and pin assignment as the DRV8662, but it appears to cost 2-3 times more. Is this correct? If so, why? I am concerned there is something I missing in the specs and would like to understand the differences between the DRV8662 and DRV2700.
I also noticed that TI recommends another part if the voltage excitation is limited to 30Vp-p (the piezos we are looking at all are limited to 30Vp-p or less). This part is the LM48560 – it is quite small, costs less than the DRV8662 and has frequency response curves out to 20kHz with capacitive loads >> 20nF. Is the LM48560 a better choice for our application in your opinion? Thank You,
Dave
