HPMD 24v23 (#1456) Heatsink and Current Sense

Support Motor controllers/drivers and motors
1

I had two questions on the HPMD 24v23 (item #1456):

  1. How can a heatsink be attached to the board? Most TO-252 heatsinks I have seen solder to pads on either side of the device (typically the same copper pad that the large tab solders to). I could install a heatsink on top of the plastic MOSFET package, but how effective would that be?

  2. I would like to utilize the ACS714 current sensor, however motor and logic grounds are isolated on my system. Optically isolating the logic signals is easy enough, but the analog output from the current sensor is another matter. Is the ACS714 ground isolated? I noticed two pads on the board labeled GND, so I was hopeful.

Thanks in advance.

2

Hello.

  1. We haven’t characterized how effective heatsinks are.
  2. I am not sure which two ground pads you are talking about. There is a schematic of the carrier at the bottom of the product page. IP- is not connected to GND. The current sensor uses a hall-effect sensor that allows the current path to be electrically isolated from the rest of the circuitry.

- Ryan

3

Hi Ryan.

Thanks for the prompt reply.

Regarding #2, sorry my original post was not clear. I want to use the ACS714 that is mounted on the HPMD 24v23 (#1456) board, not the ACS714 carrier board described on the product page you linked to.

I am familiar with the ACS714 (I have used them previously), and how the measured current path can be isolated from the rest of the circuit. My question is whether the current path is isolated on the #1456 board or not.

Thanks again,

Jeff.

4

Oh, I see. Unfortunately, h-bridge ground is not isolated from the logic ground.

- Ryan