ADLINK CM1-86DX3 PC/104 Embedded Single Board Computer Engineering Application Guide

ADLINK CM1-86DX3 PC/104 Embedded Single Board Computer Engineering Application Guide

In embedded fields such as industrial control, transportation, medical equipment, and military electronics that require strict reliability and lifecycle, the PC/104 standard has always held an important position due to its compact size, robust architecture, and long-term supply support. ADLINK's CM1-86DX3 is a PC/104 single board computer based on the DMP Vortex86-DX3 dual core SoC, which provides standard x86 compatibility while achieving excellent performance to power ratio. This article will systematically review the core characteristics, heat dissipation design points, interface configuration, and system integration considerations of the board from an engineering application perspective.

Overview of Product Positioning and Core Specifications

CM1-86DX3 adopts PC/104 standard external dimensions (90.17mm × 95.86mm), with an overall height of only 11.05mm, which is very suitable for embedded chassis with limited space. Its core is the DMP Vortex86-DX3 system level chip, with a maximum clock speed of 1GHz, integrated 512KB L2 cache, and built-in graphics processing unit (VGA/2D graphics). The onboard 2GB DDR3L non ECC memory is directly soldered, avoiding the potential poor contact issues that may occur with traditional SO-DIMM slots in vibration environments, significantly improving reliability.

In terms of storage and expansion, the board provides a SATA interface and an optional CFast slot, allowing users to choose a solid-state drive or CFast card as the boot disk according to their needs. In addition, the standard PC/104 (ISA) bus expansion interface supports traditional industrial I/O boards, ensuring compatibility with existing systems. The system only requires a single+5V DC power supply for power supply, with a typical power consumption of about 6.25W, which is very suitable for fanless designs that are sensitive to power consumption.

Design and selection of heat dissipation scheme

Heat dissipation design is the key to the long-term stable operation of embedded systems. CM1-86DX3 supports a wide temperature range of -40 ° C to+85 ° C, but must be equipped with corresponding passive heat sinks and meet specific airflow requirements.

1. Selection of radiator

ADLINK offers two passive heat sink options:

CM1-86DX3-TM-10-A5: Suitable for commercial/industrial temperature range from 0 ° C to+60 ° C.

CM1-86DX3-TM-20-A5: Suitable for a wide temperature range of -40 ° C to+85 ° C, meeting the needs of military or harsh outdoor environments.

2. Installation points

The heat sink is fixed to the top of the board with five M2.5 screws. When installing, be sure to remove the blue protective film on the surface of the heat sink pad to ensure good contact between the heating elements such as SoC, SDRAM, and BMC controller and the heat sink pad. When tightening the screws, the torque should be controlled at 2 kgf.cm to avoid damage to the PCB or chip due to excessive stress.

3. Airflow requirements

According to the official temperature airflow curve, the heat dissipation effect is closely related to the direction of airflow. Among the four airflow directions based on the radiator, direction A (along the longitudinal direction of the heat sink) usually has the best efficiency. When the ambient temperature approaches the upper limit of 85 ° C, it is necessary to ensure that at least 200 LFM of airflow passes through the heat sink. If active air cooling cannot be provided, it is necessary to reduce the rating or choose a customized cooling solution with higher performance.

Key interface configuration and signal definition

Correctly understanding and configuring onboard interfaces is the foundation of system integration. Here are a few interfaces that require special attention.

1. Serial interface (COM1-COM4)

CM1-86DX3 provides four serial ports with flexible protocol configuration capabilities:

COM1 and COM2: can be independently configured as RS-232, RS-422, or RS-485 modes through the Advanced>Serial Port menu in the BIOS. When operating in RS-485 mode, pin 1 (DATA+) and pin 3 (DATA -) act as differential pairs for data transmission and reception; Pin 5 and pin 7 can be used for auxiliary signals of RS-422. This design greatly enhances the flexibility of the board in connecting various peripherals (such as frequency converters, smart meters, PLCs) on industrial sites.

COM3 and COM4: Fixed at RS-232 level, using standard DCD, DSR, RXD and other signal definitions, suitable for connecting mice, modems or serial consoles.

2. Display interface

The board provides a 44 pin TTL/VGA composite interface (CN7), supporting dual display output of TFT LCD screen and standard VGA display. By using jumper JP1 (TFT voltage selection) and JP3 (TFT power supply voltage selection), the panel voltage can be configured to be+3.3V or+5V, compatible with multiple specifications of LCD screens. The VGA section provides an independent DDC interface (CN1702) that supports plug and play display recognition.

3. USB and GPIO

Both USB 2.0 interfaces (CN19, CN20) support overcurrent detection. In addition, the board provides 8-bit user GPIO (CN2), which can be used to read button status or control LED indicator lights. Please note that the GPIO pin level is 3.3V, and level conversion is required when connecting to an external 5V logic.