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CM4 to CM3 Adapter
⚠️ Deprecated: This page is outdated and may contain inaccurate information. It is kept for reference only.
Overview
Since the Raspberry Pi Compute Module 3 (CM3) module is in short supply, the CM4 to CM3 adapter is designed to convert CM4 module to CM3 interface.
This adapter board converts the latest Raspberry Pi Compute Module 4 (CM4) to CM3 interface, allowing CM4 to adapt to the old CM3+/CM3/CM3L series baseboard. Also Support to use CM4 with Geekworm 12mm aluminum alloy heatsink C235.
When install the CM4 module into CM4 to CM3 adapter board, please pay attention to the CM4 install directions.
Note：
- Make sure that the CM4 module is installed on the expansion board correctly before power on.
- Please pay attention to the CM4 install directions.
- The Raspberry Pi Compute Module 4 or heatsink is not included in the packing list.
Features
- Raspberry Pi Compute Module 4 interface
- 1 x CM3 interface
- 1 x Boot led(System status led indicator)
- 1 x Reboot Button
- Operating temperature: 0℃~80℃
- Dimensions: 67.6x46.5mm/2.66x1.83inch
User Manual
Why have JP1 & JP2?
The VBAT voltage range of CM3 is 2.5-5V, and the VBAT voltage of most CM3 IO boards is 3.3V or 5V, but the VBA voltage of CM4 is only 5V. When the VBAT of the CM3 IO board used is 3.3V, a DC circuit is needed; but if the VBAT of the CM3 IO board is 5V, the DC voltage will produce howling because it does not need to be boosted;
Please shorten JP1 only for CM3 IO board with VBAT voltage less than 5V, or shorten JP2 only for CM3 IO board with VBAT volgate of 5V;
But this issue has been solved in the current production batch.
Packing List
1x CM4 to CM3 Adapter
FAQ
Q1:Which GPIO can be used after use the CM4 to CM3 Adapter?
A: CM3 has 46 GPIOs, ranging from GPIO0~GPIO45; while CM4 has only 28 GPIOs, ranging from GPIO0~GPIO27; so if you want to use CM4 to replace CM3, GPIO can only use GPIO0~GPIO27, because CM4 has only 28 GPIO, please refer to the datasheet of CM4 and CM3, thanks!
Q2: Does the CM4 to CM3 Adapter support CM4 Lite?
A: Yes, you can use the CM4 to CM3 Adapter covert CM4 Lite to CM3 Lite. But please make sure your CM3 IO board is support the CM3 Lite, then you can use it.