Custom Mainboard Design for Forensic Device
I am designing a custom standalone mainboard for a forensic hardware device. This single PCB will be used in both portable and desktop enclosures
Thought for 6 sec
Got it — a single standalone mainboard intended to fit both portable and desktop forensic-device enclosures.
For this kind of board, I’d start by defining the shared core requirements before schematic capture:
- Power architecture: battery/portable input, desktop DC input, charging or power-path needs.
- Compute/control: MCU, MPU, FPGA, or SBC/module.
- Forensic interfaces: USB, SATA, PCIe/NVMe, SD/microSD, eMMC, UART/JTAG/SWD, write-blocking requirements.
- Storage/logging: local flash, removable storage, secure logs.
- Security/tamper: secure element, case-open detect, RTC, signed firmware, audit trail.
- Mechanical constraints: board outline, connector edge locations, mounting holes, enclosure-specific daughterboards or unused headers.
- Compliance/safety: ESD, surge protection, USB compliance, battery safety if portable.
- Serviceability: debug headers, test points, firmware recovery, clear labeling.
The first decision I’d make is whether this should be a single universal board with configurable population options or a mainboard plus small enclosure-specific adapter boards. For portable + desktop use, the adapter-board approach is often cleaner because high-wear connectors, battery pack interfaces, fan/display cables, and enclosure-specific IO can change without respinning the mainboard.
If you want, I can help turn this into a concrete hardware architecture and project specification next.
use pi com5 or com4 will be single board with poe power and or usbc power in female
Thought for 22 sec
Use a Raspberry Pi Compute Module 5 if available in your sourcing path; otherwise design around CM4-compatible patterns first. For a forensic device, I’d avoid a full Pi 5 SBC and use a Compute Module so the mainboard can own the power, IO protection, connectors, and enclosure fit.
Recommended baseline architecture:
- Core module: Raspberry Pi CM4/CM5 on board-to-board connectors.
- Power inputs:
- PoE input through RJ45 MagJack + PoE PD controller/module.
- USB-C female power input as a second input.
- Add ideal-diode/power-path ORing so PoE and USB-C do not back-feed each other.
- Main system rail: generate the Pi input rail from the selected source, typically 5 V with enough current headroom.
- Ethernet: route CM Ethernet to RJ45/PoE front end.
- USB-C: decide whether it is power-only, USB device, or USB host/OTG. This changes the connector wiring and protection.
- Forensic IO: place high-wear ports at enclosure edges; protect all external interfaces with ESD parts.
- Portable/desktop sharing: keep the main PCB universal, but expose headers for enclosure-specific battery/display/fan/front-panel options.
Important clarification before schematic work:
Do you want the USB-C female connector to be power-only input, or should it also carry USB data to the Pi? Also, should PoE be 802.3af ~13 W, 802.3at ~25 W, or higher-power 802.3bt?
Do you want the USB-C female connector to be power-only input, or should it also carry USB data to the Pi? Also, should PoE be 802.3af ~13 W, 802.3at ~25 W, or higher-power 802.3bt?
