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Advantech

SOM-Express

System On Module

Design Guide

Version 1.1

Summary of content (112 pages)

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Advantech SOM-Express System On Module Design Guide Version 1.
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Advantech SOM-Express Design Guide Notices The copyright on this user manual remains with Advantech Co., Ltd. No part of this user manual may be transmitted, reproduced, or changed. Other companies’ product names that may be used herein remain the property of their respective owners. The product specifications, design and this user’s manuals content are subject to change without notice. If you have any questions, please contact your merchant or our service center for clarification.
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Advantech SOM-Express Design Guide Table of Contents Chapter 1 1.1 Introduction............................................................................................9 Terminology.............................................................................................9 Table 1.1 Conventions and Terminology .......................................9 1.2 Referenced Documents.........................................................................10 Table 1.2 Referenced Documents .....................
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Advantech SOM-Express Design Guide 2.6.2 Universal Serial Bus (USB) AC Spec. ..........................................29 2.6.3 Audio AC Spec. ............................................................................29 2.6.4 VGA AC Spec. ..............................................................................29 2.6.5 IDE AC Spec.................................................................................30 2.6.6 I2C AC Spec. .....................................................................
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Advantech SOM-Express Design Guide Figure 5-10 Violation of Proper Routing Techniques....................50 Figure 5-11 Creating Unnecessary Stubs....................................50 5.3 AC Link/Azalia interface ........................................................................51 5.3.1 Signal Description.........................................................................51 Table 5.10 Audio signals description ............................................51 5.3.2 Design Guidelines...............
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Advantech SOM-Express Design Guide Figure 5-31 Bend example ...........................................................67 Figure 5-32 10/100M Ethernet Interconnection ............................68 Figure 5-33 Gigabit Ethernet Interconnection...............................68 Figure 5-34 Critical Dimensions....................................................69 5.8 TV-Out ...................................................................................................70 5.8.1 Signal Descriptions ..........
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Advantech SOM-Express Design Guide Figure 5-53 Example of SATA trace length pair matching............86 5.12 LPC........................................................................................................87 5.12.1 Signal Description.........................................................................87 Table 5-32 LPC signals description ..............................................87 5.12.2 Design Guidelines.........................................................................
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Advantech SOM-Express Design Guide 8.8.3 8.8.4 8.8.5 8.8.6 8 Heat-Sink ....................................................................................107 Figure 8-8: Heatsink Dimensions................................................107 Table 8.2: Chemistry Ingredient & Temper Designation.............108 Thermal Pad ...............................................................................108 Figure 8-8: Thermal Pad.............................................................108 Table 8.
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Advantech SOM-Express Design Guide Chapter 1 Introduction This design guide organizes and provides Advantech’s SOM carrier board design recommendations for Advantech SOM-Express modules. It specifies common mechanical and electrical characteristics in order to ensure the carrier board design meets all the requirements needed to work properly. 1.1 Terminology Table 1.
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Advantech SOM-Express Design Guide 1.2 Referenced Documents Table 1.2 Referenced Documents Document Advanced Configuration and Power Management (ACPI) Specification 3.0b Location http://www.acpi.info/spec.htm COM Express Specification http://www.picmg.org/ Ethernet(IEEE 802.3) I2C Bus Interface http://www.ieee.org/portal/site http://www.semiconductors.philips.com/ IrDA http://www.irda.org/ PCI http://www.pcisig.com/ PC104 http://www.pc104.org/technology/pc104_tech.html RS232 http://www.eia.
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Advantech SOM-Express Design Guide Chapter 2 SOM-Express Overview SOM-Express complies with COM Express standard from the PCI Industrial Computer Manufacturers Group (PICMG) which provides next generation performance of the smallest state of the art embedded modules. With a scalable solution that meets customer's advanced CPU application development needs and reduces time-to-market.
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Advantech SOM-Express Design Guide Though small in size, SOM takes care of most complicated CPU architectures and basic common circuits. Many system integrators are finding an Advantech SOM solution already covers 80% of their feature requirements. This makes SOM a powerful time and money saver. SOM + Customer Solution Board = Your Customized Platform. System On Modules save time and money.
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Advantech SOM-Express Design Guide 2.2 Specifications Advantech provides two SOM-Express modules, and each module has a different CPU type for customer to choose. Table 2.1 shows Advantech SOM-Express modules with brief descriptions. Table 2.
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Advantech SOM-Express Design Guide 2.2.1 SOM-5780 Advantech’s new SOM-5780 is the ultimate powerful SOM-Express CPU module able to drive the most demanding embedded applications requiring high performance CPU processing power & graphics support. With support for Intel® Pentium® M and Celeron® M processors & enhanced SpeedStep technology, the SOM-5780 offers developers a low power and scaleable solution that fits a range of needs.
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Advantech SOM-Express Design Guide SOM-5780 Main Features: Embedded Intel® Pentium® M/ Celeron M processor Intel Extreme Graphics 2 & PCI Express graphics Supports the upcoming primary datapath PCI Express Supports 8 host USB2.0 ports and 4 SATA Supports up to dual channel LVDS panels Table 2.
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Advantech SOM-Express Design Guide 2.2.
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Advantech SOM-Express Design Guide SOM-5782 Main Features: Embedded Intel® Core2 Duo / Core Duo / Celeron® M Processor Intel new graphics core based on GMA 950 & external PCI Express x 16 graphics interface. Supports the upcoming primary datapath PCI Express Supports 8 host USB 2.0 ports and 2 SATA ports Supports up to dual channel LVDS panels Table 2.
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Advantech SOM-Express Design Guide 2.2.3 SOM-DB5700 CD-IN CENTER/LFE ATX-POWER SURROUND AC Link HD Audio SIDESURR Codec ALC880 FRONT_OUT Primary IDE System Module LINE1/2_IN FDD(34P Standard) LPC Super IO USB 2.
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Advantech SOM-Express Design Guide 2.3 System Resources This section demonstrates resources distribution of Advantech’s SOM-Express modules, including IRQ, DMA, memory map, and I/O map. 2.3.1 SOM-5780 Resources Table 2.
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Advantech SOM-Express Design Guide Table 2.
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Advantech SOM-Express Design Guide Table 2.
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Advantech SOM-Express Design Guide Table 2.8 SOM-5780 Alternative Device Resources Alternative Device Resources COM1 3F8/IRQ4*, 2F8/IRQ3, 3E8/IRQ4, 2E8/IRQ3, Disable COM2 3F8/IRQ4, 2F8/IRQ3*, 3E8/IRQ4, 2E8/IRQ3, Disable LPT1 378/IRQ7*, 278/IRQ5, 3BC/IRQ7, Disable * Default setting 2.3.2 SOM-5782 Resources Table 2.9 IRQ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 16 16 17 18 19 19 19 23 23 Table 2.
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Advantech SOM-Express Design Guide Table 2.
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Advantech SOM-Express Design Guide Table 2.
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Advantech SOM-Express Design Guide 0xEA00-0xEA0F Intel(R) 82801GBM/GHM (ICH7-M Family) Serial ATA Storage Controller - 27C4 Intel(R) 82801G (ICH7 Family) USB Universal Host Controller 27CB Intel(R) 82801G (ICH7 Family) USB Universal Host Controller 27CA Intel(R) 82801G (ICH7 Family) USB Universal Host Controller 27C9 Intel(R) 82801G (ICH7 Family) USB Universal Host Controller 27C8 Mobile Intel(R) 945GM Express Chipset Family 0xEB00-0xEB1F 0xEC00-0xEC1F 0xED00-0xED1F 0xEE00-0xEE1F 0xEF00-0xEF07 Table 2.
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Advantech SOM-Express Design Guide Table 2.16 DC specifications for 3.3V signaling of PCI Bus Symbol Parameter Min Vcc Vih Vil Vipu Voh Vol Max Units Supply Voltage 3.0 3.6 V Input High Voltage 0.5Vcc Vcc+0.5 V Input Low Voltage -0.5 0.3Vcc V Input Pull-up Voltage 0.7Vcc - V Output High Voltage 0.9Vcc - V Output Low Voltage - 0.1Vcc V Note *1 *1. This specification should be guaranteed by design.
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Advantech SOM-Express Design Guide 2.5.1.2 Universal Serial Bus (USB) Table 2.17 Symbol Vbus Vbus VIL VIH VIHZ VOL VOH DC specification of USB signals Parameter High-power port supply voltage Low-power port supply voltage Input Low Voltage Input High Voltage(driven) Input High Voltage(floating) Output Low Voltage Output High Voltage Min 4.75 4.75 2.0 2.7 0 2.8 Max 5.25 5.25 0.8 3.6 0.3 3.6 Unit V V V V V V V Note 2.5.1.3 Audio Table 2.
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Advantech SOM-Express Design Guide 2.5.1.5 LCD Table 2.22 Symbol VIL VIH VOL VOH LCD I/O Voltage Parameter Input Low Voltage Input High Voltage Output Low Voltage Output High Voltage Min -0.5 2.0 2.4 Max 0.8 Vcc+0.5 0.55 - Unit V V V V Note Max 5.5 0 - Unit V V V Note Iol=4.0mA Ioh=-1.0mA 2.5.1.6 IDE Table 2.23 Symbol VIH VOL VOH Ultra DMA modes 1-4 (5V) Parameter Input High Voltage Output Low Voltage Output High Voltage Min 2 Table 2.24 Ultra DMA modes 5 (3.
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Advantech SOM-Express Design Guide *1. From ”Infrared Data Association – Infrared Dongle Interface v1.1” *2. Vcc=5.0V±5% 2.5.1.10 I2C Table 2.28 I2C I/O Voltage Symbol Parameter VIL Input Low Voltage VIH Input High Voltage VOL Output Low Voltage Min -0.5 Max 0.3Vdd Unit V 0.7Vdd Vdd+0.5 V 0 0.4 V Note *1. The I2C Bus Specification V2.1. *2. Vdd is the voltage which the pull-up resistor are connected. 2.5.1.11 SMBus Table 2.
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Advantech SOM-Express Design Guide 2.6.5 IDE AC Spec. Please refer to “Information Technology - AT Attachment with Packet Interface – 7 Volume 2 (ATA/ATAPI-7 V2)” Annex B.5 for the details 2.6.6 I2C AC Spec. Please refer to “THE I 2C-BUS SPECIFICATION VERSION 2.1 JANUARY 2000” for the DAC AC Characteristics 2.6.7 SMBus AC Spec. Please refer to “System Management Bus (SMBus) Specification Version 2.
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Advantech SOM-Express Design Guide Chapter 3 Pin Assignments This chapter describes pin assignments and IO characteristics for the 440 pin SOMExpress. It includes four parts (A, B, C, D). There are five types of pin assignments for COM-Express. We chose type-2 pin assignments on the SOM-Express. Please refer to the COM-Express specifications to get more information. Figure 3-1 SOM-Express Diagram Table 3.
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Advantech SOM-Express Design Guide 3.1 Row A Table 3.
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Advantech SOM-Express Design Guide 3.2 Row B Table 3.
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Advantech SOM-Express Design Guide 3.3 Row C Table 3.
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Advantech SOM-Express Design Guide 3.4 Row D Table 3.
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Advantech SOM-Express Design Guide Chapter 4 General Design Recommendations A brief description of the Printed Circuit Board (PCB) for SOM-Express based boards is provided in this section. From a cost- effectiveness point of view, a four-layer board is the target platform for the motherboard design. For better quality, a six-layer or 8layer board is preferred. 4.
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Advantech SOM-Express Design Guide 4.1.1 Four layer board stack-up Figure 4-1 illustrates an example of a four-layer stack-up with 2 signal layers and 2 power planes. The two power planes are the power layer and the ground layer. The layer sequence of component-ground-power-solder is the most common stack-up arrangement from top to bottom. L1 Signal Layer Prepreg 62 mils L2 Ground Layer Core L3 Power Layer Total Thickness 62 mils Prepreg L4 Signal Layer Figure 4-1 Four-Layer Stack-up Table 4.
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Advantech SOM-Express Design Guide 4.1.2 Six layer board stack-up Figure 4-2 illustrates an example of a six-layer stack-up with 4 signal layers and 2 power planes. The two power planes are the power layer and the ground layer. The layer sequence of component-ground-IN1-IN2-power-solder is the most common stack-up arrangement from top to bottom.
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Advantech SOM-Express Design Guide 4.2 Differential Impedance Targets for Microstrip Routing Table 4.3 shows the target impedance of the differential signals. The carrier board should follow the required impedance in this table. Table 4.3 Differential Signals Impedance Requirement Signal Type Impedance Host Clock DMI Ext Gfx-PCI Express Arch.
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Advantech SOM-Express Design Guide Chapter 5 Carrier Board Design Guidelines 5.1 PCI-Bus SOM-Express provides a PCI Bus interface that is compliant with the PCI Local Bus Specification, Revision 2.3. The implementation is optimized for high-performance data streaming when SOM-Express is acting as either the target or the initiator on the PCI bus. For more information on the PCI Bus interface, please refer to the PCI Local Bus Specification, Revision 2.3. 5.1.
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Advantech SOM-Express Design Guide 5.1.2 Design Guidelines 5.1.2.1 Differences among PCI Slots Most PCI signals are connected in parallel to all the slots (or devices). The exceptions are the following pins from each slot or device: Table 5.2 Carrier PCI Slots IDSEL CLK INTA# ~ INTD# REQ# GNT# : Connected (through resistor) to a different AD line for each slot. : Connected to a different SOM-Express PCI clock signal for each slot. : Connected to a different SOM-Express interrupt signal for each slot.
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Advantech SOM-Express Design Guide SOM-Express Module AD23 AD22 AD21 AD20 Pin C43 Pin D40 INTA# INTB# INTC# INTD# Pin C49 Pin C50 Pin D46 Pin C42 Pin D39 PCI Slot / Device 0 PCI Slot / Device 1 PCI Slot / Device 2 PCI Slot / Device 3 Pin D47 Pin A26 IDSEL Pin A26 IDSEL Pin A26 IDSEL Pin A26 IDSEL Pin A6 Pin A6 Pin A6 Pin A6 Pin B7 Pin B7 Pin B7 Pin B7 Pin A7 Pin A7 Pin A7 Pin A7 Pin B8 Pin B8 Pin B8 Pin B8 Figure 5-1 Routing PCI Slot/Device CSB Interrupt Due to different sys
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Advantech SOM-Express Design Guide Vih Vtest Vil CLK (Device 1) Tskew Tskew Tskew Vih Vtest Vil CLK (Device 2) Figure 5-2 Clock Skew Diagram 5.1.2.3 Non-necessary Signals for Individual PCI device A PCI device implemented directly on the carrier board uses a subset of the signals shown on the slot connector. Some pins on the slot connector are used for slot and PCI card management functions and are not necessary for the operation of the PCI device itself.
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Advantech SOM-Express Design Guide 5.1.2.5 SOM-Express PCI interface supply voltage The SOM-Express PCI interface is a 3.3 V signaling environment but has 5 V tolerance for I/O signals. If a universal PCI connector is used at the carrier board, a jumper design to select Vio for 5 V and 3.3 V is necessary. Otherwise, the suitable Vio voltage should be designed for a 5 V or 3.3 V connector. Table 5.6 Add-in Card Supplied Power Selection Symbol 3.3 V Connector 5 V Connector Vio 3.
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Advantech SOM-Express Design Guide Table 5.7 PCI Data Signals Routing Summary Trace PCI Routing Requirements Impedance 55 Ω +/- 10% 6 mils width, 6 mils spacing (based on stackup assumptions) Topology 2 Slots W1 = W2 = 0.5 inches, R_IDSEL = 300 to 900. 3 Slots W1 = W2 = 0.5 inches, R_IDSEL = 300 to 900. 4 Slots W1 = W2 = 0.5 inches, R_IDSEL = 300 to 900. Maximum Trace Length (unit: inch) L1 L2 L3 L4 10 1.0 10 1.0 1.0 10 1.1 1.1 1.1 5.1.3.
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Advantech SOM-Express Design Guide 5.1.4 Application Notes 5.1.4.1 REQ/GNT These signals are used only by bus-mastering PCI devices. Most SOM-Express modules do not have enough REQ/GNT pairs available to support a bus-mastering device at every slot position. A PCI arbiter design is recommended when extra REQ/GNT pairs are required. Figure 5-5 shows an example design for PCI arbiter.
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Advantech SOM-Express Design Guide 5.2 Universal Serial Bus (USB) The Universal Serial Bus (USB) provides a bi-directional, isochronous, hot-attachable Plug and Play serial interface for adding external peripheral devices such as game controllers, communication devices and input devices on a single bus. SOM-Express modules provide several USB 2.0 ports. USB stands for Universal Serial Bus, an industry-standard specification for attaching peripherals to a computer.
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Advantech SOM-Express Design Guide 5.2.2.1 Low ESR Capacitor You can hot plug USB devices. In fact, this is one of the virtues of USB relative to most other PC interfaces. The design of the USB power-decoupling network must absorb the momentary current surge from hot plugging an unpowered device. Reducing these values is not recommended. These capacitors should be low ESR, low inductance. 5.2.2.
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Advantech SOM-Express Design Guide usually allows determining the correct trace width and spacing to achieve this impedance, after the PCB stack-up configuration is known. As per usual differential pair routing practices, the two traces of each USB pair should be matched in length and kept at uniform spacing. Sharp corners should be avoided. At the SOM-Express module and connector ends of the routes, loop areas should be minimized. USB data pairs should be routed as far from other signals as possible.
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Advantech SOM-Express Design Guide 5.2.3.3 Crossing a plane split The mistake shown here is where the data lines cross a plane split. This causes unpredictable return path currents and would likely cause a signal quality failure as well as creating EMI problems. Figure 5-10 Violation of Proper Routing Techniques 5.2.3.4 Stubs A very common routing mistake is shown in Figure 5-11.
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Advantech SOM-Express Design Guide 5.3 AC Link/Azalia interface SOM-Express provides an AC Link/Azalia interface which is compliant to AC’97 Rev. 2.3 Specification and the Azalia Specification. Please establish the AC’97/Azalia CODEC on the carrier board for your application. 5.3.1 Signal Description Table 5.10 shows SOM-Express AC Link/Azalia interface signals, including pin number, signals, I/0 and descriptions. Table 5.
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Advantech SOM-Express Design Guide AC/MC/AMC SOM-Express AC_RST# AC_SDOUT AC_SYNC AC_BITCLK AC_SDIN[0] AC_SDIN[1] AC_SDIN[2] Primary Codec AC/MC/AMC Secondary Codec AC/MC/AMC Tertiary Codec Figure 5-12 AC link Connections 5.3.2.3 Azalia: Figure 5-13 shows the connections for SOM-Express Azalia signals. Azalia clocking is provided from SOM-Express via AC_BITCLK. AC_BITCLK is a 24.
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Advantech SOM-Express Design Guide 5.3.2.5 Grounding Techniques Take care when grounding back panel audio jacks, especially the line in and microphone jacks. Avoid grounding the audio jacks to the ground plane directly under the connectors. Doing so raises the potential for audio noise to be induced on the inputs due to the difference in ground potential between the audio jacks and the codec’s ground point. Figure 5-14 provides an AC‘ 97 example.
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Advantech SOM-Express Design Guide 5.3.3 Layout Guidelines 5.3.3.1 General Board Routing Recommendations ! ! ! ! ! ! ! Special consideration must be given for the ground return paths for the analog signals. Digital signals routed in the vicinity of the analog audio signals must not cross the power plane split. Located analog and digital signals as far as possible from each other. Partition the board with all analog components grouped together in one area and all digital components in another.
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Advantech SOM-Express Design Guide Carrier board Audio Codec (down) L3 R1 SOM-Express L2 L1 CONN L2 L3 R2 Modem Codec L4 MDC R3 CONN L2 Q Switch L2 L5 Audio Codec L6 Dock Figure 5-17 Azalia – AC_SDOUT/AC_SYNC/AC_BITCLK/AC_RST# Topology#1 Table 5.
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Advantech SOM-Express Design Guide Table 5.13 Azalia – AC_SDOUT/AC_SYNC/AC_ BITCLK/AC_RST# Topology #2 Trace Azalia Requirements Trace Series Impedance length Termination Resistance 55 Ω +/- 15% 4 on 7 (stripline) L1= 0.5“ R1= 39 Ω 5 on 7 (microstrip) L2≤ 0.1“ R2= 39 Ω L3= 1“ – 7“ R3= 39 Ω L4= 1 - 5“ R4= 0 Ω Signal Length Matching N/A L5= 1.5“ L6≤ 0.5“ L7= 5“ L8= 0.1“ – 6“ 5.4 VGA SOM-Express provides analog display signals.
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Advantech SOM-Express Design Guide 5.4.2 Design Guidelines VESA standards require the DDC_PWR line. Some VGA monitors do not support the DDC standard. We suggest that VGA_I2C_CK and VGA_I2C_DAT signals must connect to the CRT monitor. They can be used for plug and play and monitor-type detection when standard monitors are attached. SOM-Express VGA Connector VGA_RED VGA_GRN VGA_BLU VGA_HSYNC VGA_VSYNC D-Sub15 VGA_I2C_CK VGA_I2C_DAT Figure 5-19 VGA Connections 5.4.3 Layout Guideline 5.4.3.
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Advantech SOM-Express Design Guide 5.4.3.2 RGB Output Current Balance Path Analog R, G and B (red, green and blue) traces should be designed to be as short as possible. Careful design, however, will allow considerable trace lengths with no visible artifacts. GNDRGB is an "analog current balance path" for the RGB lines.
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Advantech SOM-Express Design Guide 5.5 LVDS 5.5.1 Signal Description Table 5-15 shows SOM-Express LVDS signals, including pin number, signals, I/0 and descriptions.
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Advantech SOM-Express Design Guide Table 5-16 LVDS Signals Trace Length Mismatch Mapping Siganl group CHANNEL A CHANNEL B Signal matching Data Pair LVDS_A[0]+ LVDS_A[0]LVDS_A[1]+ LVDS_A[1]LVDS_A[2]+ LVDS_A[2]LVDS_A[3]+ LVDS_A[3]LVDS_B[0]+ LVDS_B[0]LVDS_B[1]+ LVDS_B[1]LVDS_B[2]+ LVDS_B[2]LVDS_B[3]+ LVDS_B[3]- Clock Matching Data To Associated Clock Matching LVDS_A_CK+ LVDS_A_CK- ±10 mils ±10 mils LVDS_B_CK+ LVDS_B_CK- ±10 mils ±10 mils Clocks Associated with the channel ±10 mils ±10 mils ±10 m
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Advantech SOM-Express Design Guide 5.6 Primary IDE0 SOM-Express provides one IDE interface. 5.6.1 Signal Description Table 5-17 shows SOM-Express IDE signals, including pin number, signals, I/0 and descriptions. Table 5-17 IDE signals description Pin D13,14,15 D16 D17 Signal IDE_D[0..15] IDE_A[0..
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Advantech SOM-Express Design Guide Figure 5-24 IDE Master/Slave Handshake Signals Connection 5.6.2.2 UDMA Support Some SOM-Express modules support UDMA 33 data transfer mode. If an advanced IDE data transfer mode such as UDMA 66 is required, it requires a special 80conductor IDE cable for signal integrity. For UDMA 66 support, it is recommended the IDE bus and total cable length of carrier board do not exceed 13 inches. Total Max.
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Advantech SOM-Express Design Guide SOM-ETX IDE_D[0:15] IDE_A [ 0:2] IDE_CS#1 IDE_CS#3 IDE_IOR# IDE_IOW# IDE_REQ IDE_ACK # IDE Connector IDE_IORDY IDE_IRQ IDE_CBLID Figure 5-26 IDE0 Connections 5.6.2.4 CompactFlash Socket Implementation Notes The CompactFlash (CF) card cannot be hot-plugged (changed while the system is powered). If hot-plug support is necessary, then a PCI-based CardBus controller chip can be integrated onto the carrier board and used to control the CF socket.
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Advantech SOM-Express Design Guide 5.7 Ethernet SOM-Express supports the IEEE802.3 network interface and flexible dynamically loadable EEPROM algorithm. The network interface complies with the IEEE standard for 10BASE-T, 100BASE-T and 1000BASE-T Ethernet interfaces. 5.7.1 Signal Descriptions Table 5-19 shows SOM-Express Ethernet signals, including pin number, signals, I/0, power plane and descriptions.
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Advantech SOM-Express Design Guide Figure 5-27 and Figure 5-28 shows the 10/100M Ethernet and Gigabit Ethernet Connections. Figure 5-27 10/100M Ethernet Connections LAN Connector SOMExpress GBE0_MDI[0]+ GBE0_MDI[0]GBE0_MDI[1]+ GBE0_MDI[1]GBE0_MDI[2]+ GBE0_MDI[2]GBE0_MDI[3]+ GBE0_MDI[3]- Magnetic Module (Transformer) RJ45 GBE0_ACT# GBE0_LINK# GBE0_LINK100# GBE0_LINK1000# Figure 5-28 Gigabit Ethernet Connections 5.7.2.
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Advantech SOM-Express Design Guide 5.7.2.3 Implementation of indicators Some RJ-45 include LEDs which need 3.3 volts to drive the link and action LEDs, so we need to provide 3.3 volts on the carrier board. Link and activity LEDs can be implemented by using the SOM-Express module’s GBE0_ACT#, GBE0_LINK#, GBE0_LINK100#, and GBE0_LINK1000# pins. These pin’s sink current is intended for attachment to a LED cathode. The anode of the LED should be pulled to 3.3 volts through a resistor of 220 Ω or greater. 5.7.
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Advantech SOM-Express Design Guide Carrier board SOM-Express Differential Pairs L1 L2 On board chip Transformer L3 Differential Pairs Figure 5-30 Differential signals route example Figure 5-31 Bend example 5.7.3.2 Transformer We recommend using the integrated Magnetic Modules/RJ-45 connectors. If using the discrete Magnetic Modules and RJ-45 connector, the transformer should be placed close to the RJ-45 connector to limit EMI emissions.
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Advantech SOM-Express Design Guide Figure 5-32 10/100M Ethernet Interconnection Figure 5-33 Gigabit Ethernet Interconnection 5.7.3.3 Critical Dimensions There are two critical dimensions that must be considered during the layout phase of an Ethernet controller. These dimensions are identified in Figure 5-34 as A and B. Distance A: Transformer to RJ-45 (Priority 1). The distance labeled A should be given the highest priority in the backplane layout.
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Advantech SOM-Express Design Guide 1. Differential Impedance: The differential impedance should be 100 Ω. The single ended trace impedance will be approximately 50 Ω; however, the differential impedance can also be affected by the spacing between the traces. 2. Trace Symmetry: Differential pairs should be routed with consistent separation and with exactly the same lengths and physical dimensions (for example, width).
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Advantech SOM-Express Design Guide 5.8 TV-Out The TV-out display (TV DAC) interface consists of 3 outputs which can be used in different combinations to support component video, S-video or composite video. 5.8.1 Signal Descriptions Table 5.
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Advantech SOM-Express Design Guide 5.8.2.2 ESD diode ESD diodes are required for each TV DAC channel output. The diodes should connect between the 3.3 V power plane (from the regulator) and ground. These diodes should have a low C rating (~ 5 pF max) and a small leakage current (~ 10 uA at 120℃).The diodes should be placed to keep the inductance of the 3.3 V power rail connection as low as possible.
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Advantech SOM-Express Design Guide SOM-Express Carrier board 3.3 V TV_DAC_A Spacing >50 mils Zo=50O 150ohm Spacing >40 mils 3.3 V Chipset TV_DAC_B 150ohm 150ohm Spacing >40 mils Video Filter Zo=75O MAX=0.5" MAX=0.2" Zo=50O 3.3 V MAX=0.5" MAX=0.2" 150ohm Video Filter Connector 75 Ohm Coaxial Cable TV Zo=75O MAX=0.5" TV_DAC_C Zo=50O 150ohm MAX=0.2" Spacing >50 mils 150ohm Video Filter Zo=75O Figure 5-37 TV DAC Routing Topology 5.9 Miscellaneous 5.9.
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Advantech SOM-Express Design Guide TYPE2# X NC NC NC NC B12 PWRBTN# I B49 SYS_RESET# I B50 CB_RESET# O B24 PWR_OK I B18 SUS_STAT# O A15 A18 SUS_S3# SUS_S4# O O A24 SUS_S5# O B66 WAKE0# I B67 WAKE1# I A27 BATLOW# I B35 THRM# I A35 THRMTRIP# I TYPE1# X NC NC GND GND TYPE0# NC GND NC GND NC Pin-Out Type 1 Pin-Out Type 2 Pin-Out Type 3 (no IDE) Pin-Out Type 4 (no PCI) Pin-Out Type 5 (no IDE,PCI) The Carrier Board should implement combinatorial logic that monitors the mod
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Advantech SOM-Express Design Guide The SPKR output from the SOM-Express module is a CMOS level signal. It can control an external FET or logic gate that drives an external PC speaker. The SOMExpress modules SPKR output should not be directly connected to either a pull-up or a pull-down resistor. The SPKR signal is often used as a configuration strap for the core chipset in SOM-Express modules.
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Advantech SOM-Express Design Guide VCC Carrier board SOM-Express SMB_CLK 4 3 SMB_DAT 2 1 SMB Connecto r Figure 5-40 SMB Bus Connections 5.9.4 Power Good/Reset Input The SOM-Express Power OK Input (PWR_OK) may be attached to an external power good circuit if desired, or used as a manual reset input by grounding the pin with a momentary-contact pushbutton switch.
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Advantech SOM-Express Design Guide Carrier board SOMExpress Vcc Power monitor WDT# Vcc MR# Header Figure 5-42 Example of a watch-dog circuit 76 Chapter 5 Carrier Board Design Guidelines
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Advantech SOM-Express Design Guide 5.10 PCI Express Bus SOM-Express provides a PCI Express Bus interface that is compliant with the PCI Express* Base Specification, Revision 1.0a. It supports several general purpose PCI Express port (x1) and external graphics using PCI Express architecture (x16). For more information on the PCI Express Bus interface, refer to the PCI Express* Base Specification, Revision 1.0a. 5.10.
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Advantech SOM-Express Design Guide 5.10.2 Design Guidelines 5.10.2.1 PCI Express AC Coupling Capacitor Each PCI Express lane is AC coupled between its corresponding transmitter (TX) and receiver (RX). Figure 5-43 shows the connection for SOM-Express PCI Express signals. It is best to place AC coupling capacitors close to the transmitter (TX) of the SOM-Express board. Figure 5-43 PCI Express Interconnect Example We recommend using size 0603 capacitors.
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Advantech SOM-Express Design Guide in scenarios #1 and #3. The specification does not include any provisions to address scenario #2 ! Polarity Inversion The PCI Express spec requires polarity inversion to be supported independently by all receivers across the link, i.e. the positive signal from the transmitter (TX+) can connect to the negative signal of the receiver (RX-) in the same lane.
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Advantech SOM-Express Design Guide 5.10.2.3 Terminating Unused PCI Express Ports If a PCI Express port will not be implement on the platform, the PCIE _TX+/-[x] and PCIE_RX+/-[x] signals may be left as No Connects. Note: Where “x” is the port number left as No Connect. If no PCI Express ports will be implemented on the platform, the PCIE _TX+/- [0:5] and PCIE _RX+/- [0:5] signals may be left as No Connect and the WAKE# signal should be pulled-up to VccSus 3_3 with a 680 Ω – 1 kΩ resistor.
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Advantech SOM-Express Design Guide 5.10.3 Layout Guidelines The following represents a summary of the layout and routing guideline. 5.10.3.1 Differential pairs The PCI Express signals should be routed as differential pairs. The following is a summary of general routing guidelines for the differential pair traces. In SOM-Express platforms the PCI Express differential trace impendence target is 100 Ω ± 20%.
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Advantech SOM-Express Design Guide 5.10.3.2 Board Stack-up Considerations Table 5-27 shows the PCI Express Trace Width and Spacing for Micro-strip and Stripline base on the six layer board stack-up. Please refer to chapter 4 to get more information. Keep the required impedance based on the different board stack-up.
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Advantech SOM-Express Design Guide SOM-Express TX RX L1 L3 RX L2 TX PCI Express Device Figure 5-49 Topology #1 – SOM Express to PCI Express Device Down Table 5-28 SOM Express to PCI Express L1 Max = 14.75 inches 5.10.3.4 L2 Min = 0.25 inches Max = 14.5 inches L3 Max = 14.
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Advantech SOM-Express Design Guide 5.11 Serial ATA SOM-Express provides up to four Serial ATA (SATA) interface. 5.11.1 Signal Description Table 5-30 shows SOM-Express Serial ATA signals for general purpose, including pin number, signals, I/0, and descriptions.
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Advantech SOM-Express Design Guide 5.11.2.2 Indicated LED Implementation SOM-Express provides a signal (ATA_ACT#) to indicate SATA activity. In order for this signal to work in conjunction with Parallel ATA hard drives, it is recommended that designers implement glue logic. An example is shown in the Figure 5-52. When low, ATA_ACT# indicates SATA device activity and should activate the Hard Drive LED. When tri-stated, the signal will not activate the LED. The Hard Drive LED is active low.
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Advantech SOM-Express Design Guide ! directly to a mobile SATA connector, we recommend the trace length be 9.5 inches for microstrip routing and 7 inches for stripline routing. The SATA differential pair trace should be trace length matched. The difference of two line traces in a TX or RX differential pair should be restricted to less than 20 mils, but even less trace mismatch is encouraged. Figure 5-53 shows an example of SATA trace length pair matching.
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Advantech SOM-Express Design Guide 5.12 LPC SOM-Express provides a LPC interface to some devices like Super I/O , FWH and others. 5.12.1 Signal Description Table 5-32 shows SOM-Express LPC signals, including pin number, signals, I/0 and descriptions.
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Advantech SOM-Express Design Guide 5.12.4 Application Notes Some signals from the Super I/O, like Serial port, Parallel port, Floppy, IR, KBC, etc., can connect to SOM-Express via the LPC Bus. Figure 5-54 shows the architecture of the LPC interface. We will make some examples. You can get more information in the Super I/O data sheet. Figure 5-54 Architecture of LPC interface 5.12.4.1 Serial port Sometimes, in order to avoid EMI issues, we often separate ground to frame ground (I/O ground).
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Advantech SOM-Express Design Guide VCC SOMExpress Super I/O 1A Trace Wide Ferrite Fuse 1A Bead LPC_AD[0] Keyboard Connector Mini-dim 6P VCC LPC_AD[1] LPC_AD[2] LPC_AD[3] LPC_FRAME# LPC_DRQ[0] KBDAT KBCLK KB_DAT KB_CLK LPC_DRQ[1] LPC_SERIRQ GND LPC_CLK Digital Ground Chassis Ground Mouse Connector VCC 1A Trace Wide Mini-dim 6P Ferrite Fuse 1A MS_DAT MS_CLK Bead VCC KBDAT KBCLK GND Figure 5-56 Keyboard and Mouse connection To avoid EMI and ESD, the ground plane of the keyboard/mouse connect
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Advantech SOM-Express Design Guide 5.12.4.5 ESD Protection The PCB must incorporate protection against electrostatic discharge (ESD) events that might enter at I/O signal and electrical connection points. The goal is to prevent component or system failures due to externally sourced ESD impulses that may be propagated through both radiated and conducted mechanisms.
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Advantech SOM-Express Design Guide VCC Floppy 1k ohm Route to Minimum SOMExpress Index# Track# Write Protect# Read Data Diskette Change# LPC_AD[0] LPC_AD[1] LPC_AD[2] LPC_AD[3] LPC_FRAME# LPC_DRQ[0] LPC_DRQ[1] Super I/O LPC_SERIRQ LPC_CLK Motor on 0 Drive Select A# Drive Density Select# Head Select# DIR# Step# Drive Select B# Motor on 1 Write Data Write Enable Figure 5-58 Floppy Connection Chapter 5 Carrier Board Design Guidelines 91
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Advantech SOM-Express Design Guide Chapter 6 Power Delivery Guidelines This chapter provides the power consumption guidelines for SOM-Express modules and the ATX/AT power supply design recommendations for customer’s reference. 6.1 SOM-Express Power Consumption The power consumption of each SOM-Express module is shown below. The power consumption for different SOM-Express module power requirements will be necessary. Table 6.1 SOM-5780 Power Consumption SOM-5780 A1013 CPU : CPU760 2.
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Advantech SOM-Express Design Guide SOM-5780 A1013 CPU : CPU373 1.0GHz, Memory : Transcend DDRII 533 1GB +5VSB(A) +12V(A) Watts BIOS(1 min) 0.33 1.5 19.65 XP IDLE (1 min) 0.32 1.25 16.6 XP Standby(S1)(1 min) 0.32 1.07 14.44 XP Standby(S3)(1 min) 0.43 0 2.15 XP Run HCT- 11.2 (10 min) 0.31 1.49 19.43 5VSB power 0.42 0 2.1 Table 6.2 SOM-5782 Power Consumption SOM-5782 A1011 CPU : CPU T2500 2.0GHz Memory : Transcend DDRII 667 1GB +V5SB(A) +V12(A) Watt BIOS(1 min) 0.26 2.02 25.
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Advantech SOM-Express Design Guide 5VSB power 0.24 0 1.2 SOM-5782 A1011 CPU : CPU T2600 2.16GHz Memory : Transcend DDRII 667 1GB +V5SB(A) +V12(A) Watt BIOS(1 min) 0.24 2.02 25.44 XP IDLE (1 min) 0.25 1.57 20.09 XP Standby(S1)(1 min) 0.22 1.4 17.9 XP Standby(S3)(1 min) 0.39 0 1.95 XP Run HCT- 11.2 (10 min) 0.29 2.11 26.77 5VSB power 0.24 0 1.2 Notes: 1. Operates entirely from 12 Volt input power. 2.
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Advantech SOM-Express Design Guide 6.2 Design Guidelines 6.2.1 ATX Power Delivery Block Diagram An ATX power source will provide 12 V , -12 V , 5 V , -5 V , 3.3 V , 5 VSBY power , if other voltage is required (3.3 VSBY , LAN 2.5…. ) on the carrier board, an additional switching regulator or LDO will be necessary.
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Advantech SOM-Express Design Guide 6.2.2 AT Power Delivery Block Diagram An AT power source will provide 12 V and 5 V power. An additional switching regulator or LDO will be required to simulate the ATX power (3.3 V…) .There will be no standby voltage when an AT power source is used.
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Advantech SOM-Express Design Guide Chapter 7 Carrier Board Mechanical Design Guidelines 7.1 SOM-Express Mechanical Dimensions The PCB size of the SOM-Express module is 125mm x 95mm, COM Express Basic Module. The PCB thickness may be 2mm to allow high layer count stack-ups and facilitate a standard ‘z’ dimension between the Carrier Board and the top of the heatspreader. The holes shown in this drawing are intended for mounting the module / heatspreader combination to the Carrier Board.
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Advantech SOM-Express Design Guide 7.2 SOM Express Module Connector The module connector for Pin-out Type 2 shall be a 440-pin receptacle that is composed of 2 pieces of a 220-pin, 0.5 mm pitch receptacle. The pair of connectors may be held together by a plastic carrier during assembly to allow handling by automated assembly equipment. The connectors shall be qualified for LVDS operation up to 6.25GHz, to support PCI Express Generation 2 signaling speeds.
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Advantech SOM-Express Design Guide A source for the individual 8mm stack height 220-piin plug is AMP / Tyco 3-13184916 0.5mm pitch Free Height 220 pin 8H Plug, or equivalent, AMP / Tyco 8-1318491-6 0.5mm pitch Free Height 220 pin 8H Plug, or equivalent (same as previous part, but with anti-wicking solution applied) A source for the combined 8mm stack height 440-pin plug ( composed of 2 pieces of the 220 pin plug held by a carrier ) is: AMP / Tyco 3-5353652-6 0.
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Advantech SOM-Express Design Guide 7.5 SOM Express Module Connector Pin Numbering Pin numbering for 440-pin module receptacle. This is a top view of the receptacle, looking into the receptacle, as mounted on the backside of the module. Figure 7-5: SOM-Express Module Connector Pin Numbering 7.6 SOM-Express Carrier Board Connector Pin Numbering Pin numbering for 440-pin carrier-board plug. This is a top view, looking into the plug as mounted on the Carrier Board.
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Advantech SOM-Express Design Guide Chapter 8 Heatsink Recommended Design 8.1 Material of Heatsink The thermal conductivity of the heatsink's material has a major impact on cooling performance. Thermal conductivity is measured in W/mK; higher values mean better conductivity. As a rule of thumb, materials with a high electrical conductivity also have a high thermal conductivity. The following materials are commonly used for heatsinks: Aluminium.
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Advantech SOM-Express Design Guide Alternative material can be used at the users’ discretion. The entire heatsink assembly, including the heatsink, attach method, and thermal interface material, must be validated together for specific applications. 8.3 Attachment Method of Thermal Solution The thermal solution can be attached to the motherboard in a number of ways. The thermal solutions have been designed with mounting holes in the heatsink base.
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Advantech SOM-Express Design Guide Air flow Air flow (b) Side View (a) Top View Figure 8-2: Air Flow Direction 8.6 SOM-Express Thermal solution Specification Module should be equipped with a heat-spreader. This heat-spreader by itself does not constitute the complete thermal solution for a module but provides a common interface between modules and implementation-specific thermal solutions.
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Advantech SOM-Express Design Guide Tolerances (unless otherwise specified): Z (height) dimensions should be ±0.8mm [±0.031”] from top of Carrier Board to top of heat-spreader. Heat-spreader surface should be flat within 0.2mm [.008”] after assembly. Interface surface finish should have a maximum roughness average (Ra) of 1.6μ m[63μin]. The critical dimension in Figure 8-3 is the module PCB bottom side to heat-spreader top side. This dimension shall be 13.00mm±0.65mm [±0.026”].
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Advantech SOM-Express Design Guide Figure 8-4: SOM-Express Module Heat-Spreader The interior holes at coordinates (40, 40) and (80, 40) are tapped through holes with a M2.5 thread. The interior holes do not receive standoffs. These holes may be sealed on the module side by an adhesive backed foil, or they may be blind tapped holes with a minimum thread depth of 2.5mm. They are intended to allow additional attachment points to the heat-spreader from outside the module. 8.
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Advantech SOM-Express Design Guide 8.8 Advantech Heatsink Information 8.8.1 Vendor List Table 8.1: Vendor list Aluminum Extruded Heat-Spreader/Heat-Sink, Reference No.
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Advantech SOM-Express Design Guide Figure 8-7: SOM-Express Heat-Spreader Tolerances 8.8.
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Advantech SOM-Express Design Guide Table 8.2: Chemistry Ingredient & Temper Designation Mechanical Characteristics Alloy No. Designation Cutting Area Surface Extension Rate 6063 T5 Over 15kgf/㎜x㎜ 7% Chemistry Ingredient & Temper Designation Value SPECIFIED Si 0.4258 Fe 0.2037 Cu 0.0032 Mn 0.0059 Cr 0.0028 Mg 0.5147 Zn 0.0000 Ti 0.00263 8.8.4 Thermal Pad Figure 8-8: Thermal Pad Table 8.
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Advantech SOM-Express Design Guide 8.8.5 Screws Table 8.4 Screws Specification M2.5*6 M2.
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Advantech SOM-Express Design Guide 8.8.
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Advantech SOM-Express Design Guide Table 8.
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Advantech SOM-Express Design Guide 112 Chapter 8 Heat Sink Recommended Design