# REV D Hardware ![](images/amdc-rev-d-cover.jpg) ## Quick Links - [Changelog](https://github.com/Severson-Group/AMDC-Hardware/blob/develop/CHANGELOG.md#rev20200129d) - [GitHub Milestone](https://github.com/Severson-Group/AMDC-Hardware/milestone/4) - [Orderable Design Files](https://github.com/Severson-Group/AMDC-Hardware/tree/develop/REV20200129D) ## Description The 4th revision of the AMDC hardware is a major design change compared to the previous hardware design. REV D introduces a drastically smaller PCB form factor with a more compact layout. The PCB stack-up is increased from 4 to 6 layers to accomidate the smaller PCB area. Overall, the layout component density is increased to about 50% -- much higher than previous revisions. Functionally, the REV D design removes half the integrated analog input channels, reducing from 16 to 8 differential inputs. This saves space, but also limits the hardware capabilities since advanced motor drives often require many more than 8 analog inputs. To that end, an external sensing platform is designed which integrates with the AMDC via the new GPIO expansion ports. ```{toctree} :hidden: rev-d-bring-up rev-d-errata rev-d-pin-mapping ```