Description:
For a few years now, there is a constantly growing market for small-sized single board computers like the RaspberryPi, beagle bone black, banana Pi and so on. They find often a place when an increased amount of computing power is needed. Since the community has grown and the market volume has increased, the prices have decreased significantly.
The fully equipped mainboards like the classic RaspberryPi is, have their advantages when it comes to rapid prototyping or single-project volumes. But as soon as you want to do something more complex or also more robust, you would often like to design your own, custom PCB.
If you also want to integrate the computing power of a raspberry or similar into your custom PCB then you have two options.
- Design your own embedded computer including DDR3-Memory etc.
- Include a dedicated compute-module onto your board
Often you would stick with the second option since this solution is significantly less complex.
There are several boards already out there which come in a handy SO-DIMM form factor. you then only need to include a SO-DIMM connector onto your own, custom board. But these boards are often very powerful. For example, a RaspberryPi ComputeModule3 has a very powerful multicore CPU integrated. This increases the price of such modules significantly.
This project addresses this problem. that there is a need for a small, cheap and easy to use compute-module. The module should be able to run the latest Linux (kernel) and should come with a ready to use SD-Card image including a distribution like Debian or Ubuntu.
Technical data
| Power supply | +3.3V only |
| Current consumption | up to 1A max (t.b.d) |
| IOs | 150 (t.b.d) |
| CPU | Allwinner A13 |
| Memory | 512MB DDR3 @ 400MHz |
| Dimensions | 68.6 x 38mm |
| SD-Card | On-Board and external |
Power supply:
The module does not use the usual AXP209 PMIC. Instead, it uses two independent DC-DC converters for generating the needed voltages.
Connection:
For the connection, one can use a SO-DIMM 200 connector with AB keying.
Pin compatibility:
The DTB-A13-SOM can act as a partial RaspberryPi compute Module CM replacement. For example, the module has its LCD-Interface fully pin-compatible. Also, the SD-Card0 interface is fully pin-compatible. Also, the power supply pins (only 3.3V is needed, no need for VBAT [5V]) and USB0 is fully pin-compatible. Due to a different CPU, other pins might not be 100% compatible. But it should be at least possible to insert a A13-SOM module into a board where a CM3 was used without any damage.
Images:
I provide several images for this module. They are all built out of the mainline projects of U-Boot and the Linux-Kernel. There will be an automated build process in place soon. Furthermore, you can also build images by yourself since the Board’s defconfig will be fully upstream in a few weeks.
Progress: testing
Current rev.: A
PCB: ED1912-011-A
