Piezo driver with EBV DC2838A

Hi there, thanks for reaching out!

Before I can give you further assistance, could you clarify the following:

1.  As to whether or not you can use the EBV DC2838 - is your intent to evaluate the concept of generating 140V for the piezo load, or are you making a final design based on the LT8365* specifically?

2. In terms of current spike detection and isolation requirements - do your sensing electronics need to be completed isolated from the piezo supply, or only current sensing on a floating 140V node?

3. What current level (milliamps/amps) and switching response time (milli/micro/nano seconds) should trigger LT8365* shutdown?

Most importantly, do you have an LTSpice schematic/simulation or a block diagram of your setup and intended circuit?

*I am assuming you meant the LT8365 as that is what the DC2838A uses. We do not have a LT3565 product (unless you mean a LTC3565, but that IC does not appear to be relevant to the application here).

Many thanks!

Hi, hope all is well!

Just following up to see if you needed any clarification or additional help.

Please find below a link to download an LT8365 circuit (under tools and simulations on the LT8365 page) where a 12V input is boosted to 125V, with a sustained current of 20mA through the resistive load: https://www.analog.com/media/en/simulation-models/ltspice-demo-circuits/lt8365_boost.asc

I have clarified my previous questions as well in case they were unclear:

1. What input voltage range will be supplying the DC2838A?  This will let us confirm that the boost configuration will be the correct configuration for an output of 140V, as the input range for LT8365 is from 2.8-60V.

2. Is the '30mA peak current' you mentioned the maximum/nominal load current for the piezo element? I am having difficulty specifying what you mean by '30mA peak current'. A 5nF capacitor represents a very small load at 140V.

3. Is the LT8365 only generating a DC bias rail at a constant 140V for the piezo, or is the piezo continuously being charged and discharged to/from 140V at a specific frequency? And if so, what is that frequency?
    

If you have a block diagram or circuit you could share, it would greatly help me in understanding your system specifications and requirements.

Have a great day!