Hardware Reference

Sixfab AI HAT+ specifications

Electrical, mechanical, thermal, and software specifications for the Sixfab AI HAT+ on Raspberry Pi 5. Use it as the canonical reference when designing enclosures, sizing power supplies, or validating compatibility. Intelligented by DEEPX. Built on Raspberry Pi.

DEEPX DX-M1M DEEPX DX-M1ML PCIe Gen 3 x1 HAT+ compliant Raspberry Pi 5

AI HAT+ · Hardware Reference · Specifications · Updated 2026-05-09

What are the Sixfab AI HAT+ specifications?

The Sixfab AI HAT+ for Raspberry Pi 5 is a HAT+ specification compliant accelerator with a DEEPX DX-M1M (25 TOPS at INT8) or DX-M1ML (13 TOPS at INT8) NPU on a 65 × 56.5 mm board. It connects to the Raspberry Pi 5 over PCIe Gen 3 x1 through a 16-pin FFC cable, draws 4.8 W (DX-M1M) or 3.5 W (DX-M1ML) under sustained inference, and runs on 5 V DC delivered through the 40-pin GPIO header.

Quick reference

Headline figures at a glance. Scan this block first; full per-category detail follows below.

AI Performance 25 TOPS DX-M1M · INT8

AI Performance 13 TOPS DX-M1ML · INT8

Host Interface PCIe Gen 3 x1 lane · 16-pin FFC

Typical Power 4.8 W DX-M1M sustained · 3.5 W on DX-M1ML

Form Factor HAT+ 65 × 56.5 mm

Operating Temp 0 – 70 °C Commercial range

Technical specifications

Per-category breakdown of the AI HAT+ electrical, mechanical, and software specifications. Figures apply to both variants unless otherwise noted.

Compute

NPU (25 TOPS) DEEPX DX-M1M

NPU (13 TOPS) DEEPX DX-M1ML

Precision INT8 only

Multi-model RunAsync in dxrt

Multi-stream 4× 1080p, 25–30 FPS

Memory

DX-M1M 2 GB LPDDR4x

DX-M1ML 1 GB LPDDR4x

Speed 4266 MT/s

Access NPU-exclusive

Max model size Bounded by NPU RAM

Host interface

Protocol PCIe Gen 3 x1

Cable 16-pin FFC, EMI-shielded

Cable length 30 mm (included)

Reference clock 100 MHz

Detection Auto via HAT+ EEPROM

Power

Input 5 V DC, 40-pin GPIO

Rated current 3 A

Recommended PSU RPi 27 W (5 V / 5 A)

DX-M1M sustained 4.8 W

DX-M1ML sustained 3.5 W

Idle (loaded) 0.5 – 1 W

Deep sleep 0.1 – 0.2 W (PCIe L1.1)

System total ~13 – 15 W

Mechanical

PCB size 65 × 56.5 mm

Z-height 6.56 mm (no heatsink)

Mounting M2.5 × 4

Form factor HAT+ specification

Weight [NEED FROM SIXFAB]

Environmental

Operating temp 0 – 70 °C

NPU surface 85 °C burn-in (heatsink)

Cooling Passive heatsink (default)

Deployment Indoor, commercial-grade

Software

Host OS Raspberry Pi OS (Bookworm, 64-bit)

Runtime dxrt-runtime

SDK C++ & Python (DXNN)

Compiler input ONNX (export from PyTorch, TF, Keras, Ultralytics)

Camera stack libcamera, picamera2

Compiler DX-COM (x86_64 Ubuntu)

Variants

Both variants share the identical PCB; only the NPU chip installed at the factory differs. Driver, runtime, and SDK are identical, so applications run on either variant without code changes.

Specification

DX-M1M (25 TOPS)

DX-M1ML (13 TOPS)

NPU rating

25 TOPS at INT8

13 TOPS at INT8

Onboard memory

2 GB LPDDR4x

1 GB LPDDR4x

YOLOv8n with PPU

~35 FPS

Untested

Multi-stream capacity

4× 1080p, 25–30 FPS

Untested

Typical power

4.8 W

3.5 W

The driver detects the installed chip automatically at boot. The practical differences are NPU memory capacity, which bounds maximum model size, and peak inference throughput. NPU memory is exclusive to the accelerator — the Raspberry Pi 5 CPU cannot directly read or write it.

Methodology: YOLOv8n at 640×640 with Post-Processing Unit support, measured on Raspberry Pi 5 (8 GB), dxrt-runtime over PCIe Gen 3 x1.

Connectors

Two onboard interfaces plus an internal HAT+ ID EEPROM. The 40-pin GPIO header and the 16-pin FFC link are both required for operation.

40-pin GPIO header

Type 2×20 female, 2.54 mm pitch

Power Pins 2, 4 (5 V) · 1, 17 (3.3 V)

ID bus Pins 27, 28 (HAT+ EEPROM)

Ground 8 pins

Mates with the Raspberry Pi 5's male GPIO header. All pins not consumed by the AI HAT+ pass through and remain free for user code or stacked HATs. See Pinout & GPIO for the full pin map.

Required Pass-through

PCIe FFC connector

Type 16-pin FFC, EMI-shielded

Cable 30 mm (included)

Protocol PCIe Gen 3 x1

Signal 0.8 – 1.0 V_p-p HSDS

Carries the PCIe Gen 3 x1 differential pairs, the 100 MHz reference clock, and the power-enable signal between the Raspberry Pi 5 and the DEEPX NPU. The cable end labelled RPi5 plugs into the Raspberry Pi 5; the end labelled HAT plugs into this connector.

Required Cable included

HAT+ ID EEPROM (I²C)

Bus I²C ID (BCM 0 / 1)

Pull-ups 3.9 kΩ (pre-fitted)

Pins 27 (ID_SD) · 28 (ID_SC)

Spec HAT+ compliant

An onboard I²C EEPROM is connected to the Raspberry Pi 5's ID bus through pre-fitted pull-up resistors. At boot, Raspberry Pi OS reads the EEPROM and automatically loads the correct device tree overlay for the DEEPX NPU.

Internal Auto-detected

LED indicators

A single RGB LED on the top surface of the AI HAT+ provides visual feedback about board and NPU state. Detailed runtime telemetry is available through dxrt-cli and dxtop — see System Monitoring.

Green · Solid

Ready

Driver loaded, NPU initialised and ready to accept inference requests.

Blue · Blinking

Inference

NPU actively executing a model. Blink rate reflects inference activity.

Orange · Solid

Thermal warning

NPU core temperature approaching the thermal limit. Add cooling immediately.

Red · Solid

Error

Driver fault or firmware load failure. Run dxrt-cli -s to diagnose.

Cooling

During burn-in testing with a heatsink installed, the DEEPX NPU surface reached 85 °C under sustained 100% load at 25 °C ambient. The board ships without cooling hardware fitted; selection depends on workload and enclosure.

Recommended

Passive heatsink

Apply a heatsink with a thermal pad to the NPU chip. Fits inside slim enclosures, makes no noise, and handles the typical AI HAT+ workload. Suitable for most deployments and well-ventilated enclosures.

Pi 5 Active Cooler

Install the official Raspberry Pi Active Cooler on the Pi 5 before mounting the AI HAT+. Keeps the Pi 5 SoC out of thermal throttling, which the AI HAT+ would otherwise trap heat over.

Mechanical dimensions

Compliant with the official Raspberry Pi HAT+ mechanical specification. See Quickstart for mount-and-cable instructions.

Board dimensions

Length 65 mm (long edge)

Width 56.5 mm (short edge)

Z-height 6.56 mm (no heatsink)

Mounting holes M2.5 × 4 (HAT+ spec)

Standoff height Per RPi 5 GPIO clearance

AI HAT+ mechanical drawing: 65 × 56.5 mm board with M2.5 mounting holes, 40-pin GPIO header, and 16-pin FFC connector annotated.

Compliance

Regulatory and safety certification status for the AI HAT+. Status reflects what has been confirmed by Sixfab R&D as of this revision.

CE · Pending FCC · Pending RoHS · Pending EMI/EMC · Pending

Safety & handling

Safe installation and operation of the AI HAT+ relies on three things: powering down before any mechanical work, treating the board as an ESD-sensitive device during handling, and using a power supply rated for the combined Raspberry Pi 5 + AI HAT+ load.

Always power off the Raspberry Pi 5 completely and disconnect the USB-C cable before installing or removing the AI HAT+, mating or unmating the 16-pin FFC cable, or attaching a heatsink. Inserting or removing the board while powered can permanently damage both the AI HAT+ and the Raspberry Pi 5 through hot-insertion current spikes on the PCIe and power rails.

Mechanical installation

Finger-tight standoffs only. Use the M2.5 standoffs and screws supplied with the Raspberry Pi 5 or the AI HAT+ kit. Hand-tighten them — do not use power tools or apply torque beyond what is needed to remove play. The Raspberry Pi 5 PCB has no threaded mounting holes, so the threads live in the standoffs themselves; over-torquing can strip the standoff threads or crack and damage the plastic-headed screws.
Seat the GPIO header fully and squarely. The 40-pin header carries 5 V power, ground, and the HAT+ ID bus. A partially seated header can cause intermittent power, failed boot, or EEPROM read errors that prevent the device tree overlay from loading.
FFC cable orientation matters. The two ends of the supplied cable are not interchangeable. The end labelled RPi5 goes into the Raspberry Pi 5's external PCIe connector; the end labelled HAT goes into the AI HAT+ PCIe FFC connector. Match the contact-side arrow to the connector orientation. When the cable is seated correctly, the Sixfab logo printed on it faces outward, away from the boards.
No physical buttons. There are no reset, power, or user-programmable buttons on the board. Power is gated by the PCIe Power Enable (PWR_EN) signal driven by the Raspberry Pi 5.
No external power input. Do not attempt to power the board from an external source. Power flows exclusively through the 40-pin GPIO header from the Raspberry Pi 5.

ESD precautions

Handle the board by its edges and avoid touching the onboard components, connector contacts, and header pins with bare hands. Observe normal anti-static precautions when unpacking and installing.

Thermal & operating environment

Indoor commercial use. The AI HAT+ is a commercial-grade electronic device intended for indoor deployment. Outdoor use requires a sealed enclosure addressing moisture, temperature, and ventilation.
Operate within the rated range. Ambient temperature 0 – 70 °C. NPU surface temperature stays within the burn-in target of 85 °C with a heatsink fitted under sustained 100% load at 25 °C ambient. Higher ambients or sealed enclosures may require active cooling — see Cooling.
Do not run without thermal interface. Even at typical inference loads, the DEEPX NPU benefits from a thermal pad-coupled heatsink. Running bare can cause thermal throttling within minutes under continuous workload.

The minimum recommended PSU is the Raspberry Pi 27 W USB-C PD Supply (5 V / 5 A). Standard 5 V / 3 A (15 W) phone chargers will trigger under-voltage warnings, throttle the NPU, and may reboot the system during inference. A yellow lightning-bolt icon in the Raspberry Pi OS taskbar confirms insufficient power.