DFRobot - Raspberry Pi Compute Module 4 IoT Router Carrier Board Mini

This dual-Gigabit router carrier board turns a Raspberry Pi Compute Module 4 into a compact foundation for an OpenWrt router, IoT gateway or home networking project. Two Gigabit Ethernet ports combine the CM4's native network interface with a PCIe-connected network controller, keeping both wired connections on one 55x62mm board. A 26-pin GPIO header and USB 2.0 interface extend the build beyond routing to sensors, actuators and compatible peripherals. OpenWrt, Raspberry Pi OS and Ubuntu Server support offer flexibility for network and IoT applications. A Raspberry Pi Compute Module 4 is required and purchased separately.

Dual Gigabit Ethernet with a PCIe Network Interface

This CM4 carrier board provides two wired Gigabit Ethernet connections: ETH1 uses the Compute Module 4's built-in interface, while ETH2 uses a PCI Express 1000BASE-T NIC. This arrangement provides a compact starting point for separating upstream and downstream network connections in a router build. The second network connection uses PCIe rather than a USB Ethernet adapter, leaving the USB 2.0 data interface available for other peripherals. Gigabit port capability describes the interfaces; actual routing throughput depends on the complete system.

OpenWrt Routing with Linux Software Flexibility

This IoT router carrier board supports the provided OpenWrt router system, allowing a CM4-based build to be configured for routing. Compatibility with Raspberry Pi OS, Ubuntu Server and other supported Raspberry Pi systems also opens a path to gateway and home IoT applications. Processing comes from the separately installed CM4 and its BCM2711 quad-core 1.5GHz Cortex-A72 processor. The carrier board supplies networking and expansion interfaces, while the selected operating system and configuration determine the finished system's functions.

55x62mm Form Factor with GPIO and USB Expansion

This compact carrier board retains a 26-pin Raspberry Pi-compatible GPIO header for connecting suitable sensors, actuators and cooling accessories. A USB-C data port provides USB 2.0 High Speed connectivity for compatible storage devices, printers, Wi-Fi adapters or LTE modules, while a separate USB-C port supplies power. The microSD slot supports CM4 modules without eMMC. These interfaces support customized builds in a small footprint, with USB-C 5V/3A power specified for the board.

Important:

• The board-socket of CM4 is fragile, please align the direction and then press it down. It is recommended not to repeatedly plug and unplug the CM4 module.
• Make sure the CM4 installation direction is correct before powering up.
• Requires Raspberry Pi Compute Module 4 (CM4), not included.

Connect Diagram

Dimension

• Carrier board for the Raspberry Pi Compute Module 4 series; CM4 not included
• Dual Gigabit Ethernet through CM4 native networking and a PCI Express 1000BASE-T NIC
• Compact 55x62mm board for router and IoT gateway builds
• Supports OpenWrt, Raspberry Pi OS and Ubuntu Server
• 26Pin Raspberry Pi-compatible GPIO for suitable sensors, actuators and cooling accessories
• Separate USB-C power and USB 2.0 data ports
• microSD slot for modules without eMMC

• Compatible Module: Raspberry Pi Compute Module 4 series
• Ethernet:

          ETH1: Compute Module 4 Built-In

          ETH2: PCI Express 1000BASE-T NIC

• USB:

          1x USB-C: Power only

          1x USB-C: USB 2.0 High Speed

• Storage Card: microSD slot (Only modules without eMMC supported)
• GPIO: 26Pin GPIO compatible with Raspberry Pi
• Power Supply: USB-C 5V/3A
• Operating Temperature: 0℃~80℃
• Dimension: 55x62mm/2.17x2.44”

• Compute Module 4 IoT Router Carrier Board Mini x1