QSXM

Solder modules can be used just like any other component

Hardware and software integration of the newest 64-bit ARM-processor is becoming increasingly more sophisticated. Integrating everything on a single board can create some engineering challenges. Once a fully custom SoC-based board is built, it can’t be modified without delay and expense. That’s why it’s vital to know what its destination is before you design it. Despite this precaution, porting Linux or another OS to the custom hardware is an onerous task. To overcome this limitation, a SoM offers much more flexibility as the porting is already done. To further reduce costs, most projects are turning to module-based systems to increase time available for application development, reduce complexity and allow designers to focus on their core competencies.

Solder modules can be used just like any other component, and do not need to be handled and inserted manually like a SODIMM. With increasing demands on miniaturization, a SODIMM module requires more space and this can be important. The smallest soldered modules are only 27mm² (1.1″) and this is the smallest space on which it is physically possible to mount the basic components.

In all types of designs, the connector has its cost. Even a SODIMM200 connector can cost a couple of dollars and push-fit connectors can cost a lot more. Soldering offers considerable strength and therefore the components are less vulnerable to shock and vibration.

The solder-down module’s integral ground plane provides a defined return path, avoiding ground loops and allowing efficient routing of tracks with low EMI. High-speed differential signals can be easily routed on a single layer. The ground plane also aids heat transmission to the baseboard, reducing the need for heat sinks.

In projects with BGA solutions, designers might face various problems. BGAs are very good for density, but they need high precision and it can only be inspected by through x-ray. SoMs in contact with the edges prove to be a better solution as it is possible to visually inspect the connections.

Pre-programmed

All modules will be shipped with a pre-programmed bootloader by default. To speed up the production process, the modules can also be pre-programmed to customer specifications. JEDEC version 5.0 introduces “Production State Awareness” to help avoid possible data corruption during soldering. Only a predefined part of the whole device’s available space can be supported by this feature.