Small carrier board for Raspberry Pi CM4
I will describe the project and give links to download the v1.0 (RC1) files
Writing articles is not my thing, I’d rather have professionals do it:
Article on tomshardware.com (link)
Article on hackster.io (link)
v1 is available for purchase: GroupGets US
A short review from Jeff Geerling:
What do we have on the board:
- 5v (in and out)
- 3.3v (limited by CM4)
- GPIO 14, 15 (UART) (replaced with GPIO 8, 9 or UART4 in MinCab v3)
- GPIO 2, 3 (I2C)
- GPIO 18 (PWM 1)
- GPIO 13 (PWM 0)
- GPIO 4, 12 (Digital I/O)
- LEDs: Power and active
- USB-C Power Delivery
- SD card port for CM4 lite (in MinCab v2 and v3)
- CP210x USB to UART Bridge (in MinCab v3)
The funniest thing is the parts list, which means that only the port itself is required, and everything else is basically optional:
MinCab v1 BOM:
- Port for CM4: Hirose DF40C-100DS-0.4V (most important apart from the PCB)
- Capacitor C1, 667-EEF-CX0J101R (recommended for thin and/or long USB power cables)
- C2-C5 capacitors, 10uF, 0805 or 0603 (similar to previous point)
- J1, USB-C port GCT_USB4105-GF-A
- R1-R2, 5.1k, 0603, Resistors required for USB-C Power Delivery
- D1-D2, 0603, LEDs
- U1, Power LED buffer, 74LVC1G07SE-7
- R3-R4, 1k, 0603, Resistors for LEDs
- 2x Wurth Elektronik Standoffs 9774015151
MinCab v2 BOM:
- Port for CM4: Hirose DF40C-100DS-0.4V (most important apart from the PCB)
- Capacitor C1, 667-EEF-CX0J101R (recommended for thin and/or long USB power cables)
- C2-C5 capacitors, 10uF, 0805 or 0603 (similar to previous point)
- J1, USB-C port GCT_USB4105-GF-A
- J2, SD card port Molex 47571-0001
- R1-R2, 5.1k, 0603, Resistors required for USB-C Power Delivery
- D1-D2, 0603, LEDs
- U1, Power LED buffer, 74LVC1G07SE-7
- U2, Power Switch RT9742GGJ5 (needed for SD card)
- R3-R4, 470-1k, 0603, Resistors for LEDs
- R5, 12k, 0603 Resistor, pull up for U2 (needed for SD card)
- 2x Wurth Elektronik Standoffs 9774015151
MinCab v3 BOM:
- Port for CM4: Hirose DF40C-100DS-0.4V (most important apart from the PCB)
- Capacitor C1, 667-EEF-CX0J101R (recommended for thin and/or long USB power cables)
- C2-C5 capacitors, 10uF, 0805, or 0603 (similar to the previous point)
- J1, USB-C port GCT_USB4105-GF-A
- J2, SD card port Molex 47571-0001
- R1-R2, 5.1k, 0603, Resistors required for USB-C Power Delivery
- D1-D2, 0603, LEDs
- U1, Power LED buffer, 74LVC1G07SE-7
- U2, Power Switch RT9742GGJ5 (needed for SD card)
- C6, capacitor 10uF, 0603 (needed for USB-Serial)
- R3-R4, 470-1k, 0603, Resistors for LEDs
- R5, 12k, 0603 Resistor, pull up for U2 (needed for SD card)
- R6, 22k, 0603 Resistor (needed for USB-Serial)
- R7, 47k, 0603 Resistor (needed for USB-Serial)
- R8, 1k, 0603 Resistor (needed for USB-Serial)
- C7, capacitor 4.7uF, 0603 (needed for USB-Serial)
- C8, capacitor 100nF, 0603 (needed for USB-Serial)
- IC1 – CP2102N-A02-GQFN20 (USB to serial)
- 2x Wurth Elektronik Standoffs 9774015151
The original version (the red one) is generally fully functional, and I only made minor adjustments to the mounting holes for the CM4 stands and the tracks on the board. The new board looks like this (I’ll add pics after soldering):
The project is available on GitHub:
I’m a systems engineer in JetBrains company. Uptime Lab founder. I’m glad to see you on my website! I hope you find my content useful. Please subscribe to my Instagram and Twitter. I post the newest updates there.
First!
Jk, awesome collection of the information!
What was your main usecase for the mini board?
Knowing it has USB and gpio, what was the focus?
Wireless controller, remote access, wireless access for management?
It hasn’t USB (only power).
But UART and some GPIO, so you can use it for a smart home for an example.
Hi Ivan,
I really like the work you are doing!
One quick (noob) question though; Since I could use the UART Pins for 5V power supply – when retraced, can the USB-C port be re-used for data, i.e. USB-OTG then? The small form factor is really appealing, and makes me wanna go off-grid with this.
All the best!
Greg
*Update*
Just learned that the high speed port side of the CM4 is left unused in this minimal design – never mind then.
Hi Ivan,
This is a very nice design. It’s very suitable for headless cm4 setup as a server / IoT controller mainly in the cybersecurity field. I just wanna ask if my company wanna use/modify the design from your GitHub, what is the requirement (Tribute, Permission, Copyright, Collaboration)?