EDM1-IMX6 Version Comparison

Introduction

We first introduced EDM in 2013 with the EDM1 compact form-factor family featuring the NXP i.MX6 SOC (EDM1-CF-IMX6). This small module (60mm x 82mm) utilizes an MXM3 edge connector and provides a complete embedded processing system on a single module.

In 2016, we introduced an updated version of the EDM1 IMX6 family, called EDM1-IMX6 PLUS. This module features significant upgrades including an on-board PMIC and option for 802.11AC wireless.

In 2018, we further improved the module design by replacing the Broadcom-based wireless module with a fully certified module based on Qualcomm and manufactured in-house by TechNexion. This not only improves performance, but increases product longevity while providing a certfied wireless solution.

Feature Comparison

Notable Differences

In this section, we describe the most notable differences between the EDM1-CF-IMX6 and the later module versions. The main differences are the on-board power, the on-board wireless module, CAN support, and the Gigabit Ethernet PHY.

On-board Power

The i.MX6 SOC and other circuitry on the module requires a number of different voltages to power them. The EDM1-CF-IMX6 employs a discrete power supply solution, which means that independent regulators generated the required voltages. This has the advantage of being a low-cost and robust solution, but does not provide for advanced power management features such as dynamic voltage scaling or power down modes.

On the EDM1-IMX6PLUS, we replaced the discrete power solution with a power management IC, or PMIC. This IC integrates nearly all of the power supplies required for the module, and allows for dynamic voltage scaling and power down modes.

Gigabit Ethernet PHY

The onboard Ethernet PHY on the original modules is the AR8031, and on the update PLUS modules we use an AR8035. The AR8035 is lower-cost than the AR8031 and does not support Synchronous Ethernet (SyncE) or IEEE1588 at the PHY level. For the vast majority of applications, these features are not needed.

Updated in 2022, due to supply chain challenges, the EDM1-IMX6 was updated with a Realtek PHY (RTL8211). No hardware changes to the baseboard are necessary, but software changes are required in order to implement the PHY driver within the kernel and bootloader, as well as to properly reset the PHY. For a list of changes, please see Software Migration for products with Realtek PHY.

CAN PHY

The original EDM1-CF-IMX6 family optionally incorporates a CAN PHY on the module itself. This translates the low-voltage single-ended TX and RX signals from the two CAN interfaces on the i.MX6 SOC into 5V bidirectional differential signals required for CAN. In the new EDM1-IMX6PLUS, as well as in the original EDM1-CF-IMX6 family without CAN populated, the single-ended CAN signals are routed directly to the edge connector at the same pin locations. This means the designer will design the CAN PHY circuit on the baseboard, or utilize the CAN signals for other purposes such as GPIO.

If you utilize CAN in your current design and want to migrate to the EDM1-IMX6PLUS family from a CAN-enabled EDM1-CF-IMX6, you will need to redesign your baseboard to incorporate the CAN PHY. As CAN bus operates at 5V signal levels, you should not insert an EDM1-IMX6PLUS module into a slot that is directly connected to a CAN bus as these signals could cause damage to the SOC on the module.

Software Updates

When migrating from the EDM1-CF-IMX6 to the newer EDM1-IMX6PLUS, you need to update or otherwise patch your Linux kernel. This is because we added support for the PMIC and newer wireless modules and utilize different IO signals in some of the interfaces such as the Gigabit Ethernet PHY.