Intel Thin Mini-ITX Guide

Thin Mini-ITX Based PC
System Design Guide
All In One, Tiny PC
December 2012
Revision 1.2

2 Thin Mini-ITX Based PC System Design Guide
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Copyright © 2012, Intel Corporation.

Thin Mini-ITX Based PC System Design Guide 3
Contents
1Introduction ...................................................................................................... 8
1.1 Purpose / Scope ..................................................................................... 8
1.2 Overview ............................................................................................... 8
1.2.1 All In One PCs ........................................................................... 9
1.2.2 Tiny PCs ..................................................................................10
1.3 Terminology ..........................................................................................11
1.4 Reference Documents.............................................................................12
2Thin Mini-ITX Internal Electrical Interfaces...........................................................13
2.1 Common Connector List..........................................................................13
2.2 Flat Panel Display ..................................................................................14
2.2.1 LVDS ......................................................................................14
2.2.2 eDP (VESA Embedded Display Port™) .........................................17
2.2.3 Flat Panel Display Brightness .....................................................19
2.2.4 On Screen Display (OSD)...........................................................20
2.3 Audio ...................................................................................................21
2.3.1 Front Panel Audio .....................................................................21
2.3.2 Internal Stereo Speakers ...........................................................22
2.3.3 Digital Microphone ....................................................................23
2.4 SATA....................................................................................................24
2.5 Internal USB .........................................................................................24
2.5.1 Front Panel Dual USB 2.0 Header ...............................................24
2.5.2 Internal Dual USB 2.0 Header ....................................................25
2.5.3 Internal Single USB 2.0 Header ..................................................26
2.5.4 Internal USB 3.0 Header............................................................26
2.6 Front Panel (Buttons, LEDs) ....................................................................28
2.7 Internal Power Input ..............................................................................29
2.8 Fans.....................................................................................................31
2.8.1 CPU Fan ..................................................................................31
2.8.2 System Fan .............................................................................31
2.9 Consumer Infrared Receiver ....................................................................32
2.10 Wireless Bluetooth .................................................................................32
2.11 Monitor Switch ......................................................................................32
3Power Supply ...................................................................................................34
3.1 External AC Adapter ...............................................................................34
3.2 External Power Connector for Socketed CPU Based Systems........................34
4Thermals & Acoustics ........................................................................................36
4.1 General Thermal-Acoustics Considerations ................................................36
4.1.1 Blowers ...................................................................................37
4.1.2 Fan Speed Control and CPU Throttling .........................................37
4.1.3 Vent Free Area Ratio .................................................................40
4.1.4 Dust Considerations ..................................................................40
4.2 Environmental and Skin Temperature Limit Recommendations ....................40
4.3 Motherboard Component Cooling .............................................................40
4.3.1 Memory Cooling .......................................................................40

4 Thin Mini-ITX Based PC System Design Guide
4.3.2 Platform Controller Hub (PCH) Cooling ........................................41
4.3.3 Voltage Regulator Cooling..........................................................41
4.4 Acoustics ..............................................................................................42
5Mechanical.......................................................................................................44
5.1 CPU Mechanicals ....................................................................................44
5.2 Internal Motherboard Header Locations ....................................................45
5.3 System Cables and Connectors................................................................46
5.3.1 System Cable Kitting.................................................................46
5.4 CPU Thermal Solution and System Fan Mechanical Interface .......................46
5.5 Thin Mini-ITX I/O Shield .........................................................................50
5.6 Industrial Design, System Layout, and Usability Considerations ...................51
5.6.1 AIO Specific System Mechanicals ................................................52
6Low Profile Reference Heat Pipe Thermal Solution .................................................53
6.1 General Volumetrics / Requirements ........................................................53
6.2 Reference Design CPU Thermal Solution ...................................................53
7Reference System Layouts .................................................................................55
7.1 Thin Mini ITX Based System Design..........................................................55
7.1.1 General System Design Considerations........................................55
7.2 Reference Core Components Layouts........................................................56
7.3 Thermal Test Method..............................................................................65
7.3.1 Components Used for Testing.....................................................65
7.3.2 Stress Software........................................................................66
7.3.3 Temperature Measurement Locations ..........................................67
Figures
Figure 1-1. Thin Mini-ITX Applications ................................................................. 9
Figure 1-2. Mini-ITX (left) vs Thin Mini-ITX (right) ...............................................11
Figure 2-1. 40-pin LVDS Header ........................................................................15
Figure 2-2. 40-pin eDP MB Header .....................................................................17
Figure 2-3. PC & Software Brightness Control: ....................................................19
Figure 2-4. FPD Brightness Header ....................................................................19
Figure 2-5. Front Panel Audio Header .................................................................21
Figure 2-6. Internal Stereo Speakers Header.......................................................22
Figure 2-7. DMIC MB Header.............................................................................23
Figure 2-8. 2x5 USB 2.0 Header (Keyed at Pin 9) ................................................24
Figure 2-9. 2x5 USB 2.0 Header (Keyed at Pins 9 and 10) ....................................25
Figure 2-10. 1x5 USB 2.0 Header ......................................................................26
Figure 2-11. 2x10 USB 3.0 Header.....................................................................26
Figure 2-12. USB 3.0 Header Orientation ............................................................28
Figure 2-13. Front Panel Main Header.................................................................28
Figure 2-14. Internal Power Header ...................................................................29
Figure 2-15. 4-Pin CPU Fan Header ....................................................................31
Figure 2-16. CIR Receiver Header ......................................................................32
Figure 2-17. Monitor Switch Header ...................................................................32
Figure 3-1. External Power Connector for Socketed CPU Based Systems .................35
Figure 4-1. Example of Voltage Regulator Induced Throttling ................................38
Figure 4-2. Example of a Typical CPU DTS Readout When Not Throttling.................38

Thin Mini-ITX Based PC System Design Guide 5
Figure 4-3. CPU Die Temperature Induced Throttling............................................39
Figure 4-4. Air Temperature Increase Across Memory...........................................41
Figure 4-5. ECMA-74 Extract –Figure C.4c .........................................................42
Figure 4-6. ECMA-74 Extract –Figure C.4d .........................................................43
Figure 4-7. ECMA-74 Extract –Figure C.4a .........................................................43
Figure 5-1. CPU Location and Additional Keep In Zones ........................................44
Figure 5-2. Header Zones .................................................................................45
Figure 5-3. Blower and Heat Exchanger Retention Locations for Two Blower
Configuration Option 1 ................................................................................47
Figure 5-4. Blower and Heat Exchanger Retention Locations for Two Blower
Configuration Option 2 ................................................................................48
Figure 5-5. Blower and Heat Exchanger Retention Locations for a Single Blower
Configuration .............................................................................................49
Figure 5-6. Minimum Blower Gap .......................................................................50
Figure 5-7. Example Thin Mini-ITX I/O Shield ......................................................51
Figure 6-1. Reference Side and Top View Dimensions for Low Profile Reference
Thermal Solution ........................................................................................54
Figure 6-2. Reference Blower Mounting Flange Standoff Height as Measured from the
Bottom of the Flange ..................................................................................54
Figure 7-1. Core Component Layout –Example A ................................................56
Figure 7-2. Core Component Layout –Example B ................................................57
Figure 7-3. Core Component Layout –Example C ................................................58
Figure 7-4. Core Component Layout –Example D ................................................59
Figure 7-5. Core Component Layout –Example E ................................................60
Figure 7-6. Core Component Layout –Example F.................................................61
Figure 7-7. Core Component Layout –Example G (Effective Single Blower Option) ..62
Figure 7-8. Core Component Layout –Example H (Effective Single Blower Option) ..63
Figure 7-9. Core Component Layout –Example H (Effective Single Blower Option) ..64
Figure 7-10. Power Thermal Utility Example ........................................................66
Tables
Table 1-1. Common AIO Features in Thin Mini-ITX Based AIO PCs .........................10
Table 1-2. Terms and Descriptions.....................................................................11
Table 1-3. Reference Documents .......................................................................12
Table 2-1. Internal Motherboard Connectors .......................................................13
Table 2-2. 40-pin LVDS Header Pin-Out..............................................................15
Table 2-3. 40-pin eDP Header Pin-Out................................................................18
Table 2-4. 8-pin FPD Brightness Header Pin-Out ..................................................19
Table 2-5. Passive AC’97 Front Panel Audio Header Pin-Out ..................................21
Table 2-6. HD Audio Front Panel Audio Header Pin-Out.........................................21
Table 2-7. Internal Stereo Speakers Header Pin-Out ............................................23
Table 2-8. DMIC Header Pin-Out........................................................................23
Table 2-9. 2x5 USB 2.0 Header (Keyed at Pin 9) Pin-Out ......................................24
Table 2-10. 2x5 USB 2.0 Header (Keyed at Pins 9 and 10) Pin-Out ........................25
Table 2-11. 1x5 USB 2.0 Header Pin-Out ............................................................26
Table 2-12. 2x10 USB 3.0 Header Pin-Out ..........................................................27
Table 2-13. Front Panel Main Header Pin-Out ......................................................29
Table 2-14. Internal Power Header Pin-Out .........................................................30
Table 2-15. Monitor Switch Header Pin-Out.........................................................33
Table 4-1. Environmental and Skin Temperature Limit Recommendations ...............40

6 Thin Mini-ITX Based PC System Design Guide

Thin Mini-ITX Based PC System Design Guide 7
Revision History
Revision
Number
Description
Revision Date
1.2
USB 3.0 added
eDP section added
General clarifications in Section 2
December 2012
1.1
Minor updates to align with Compliance Requirements
Section 2.2.1 LVDS
Section 7.4 SATA
Section 2.5 USB
Section 2.6 Front Panel
Section 2.7 Internal Power Input
Section 3 Power Supply
August 2012
1.0
Initial release
April 2012
§

Introduction
8 Thin Mini-ITX Based PC System Design Guide
1Introduction
1.1 Purpose / Scope
This document outlines possible solutions to creating a system utilizing a Thin Mini-ITX
motherboard, as specified in the Mini-ITX Addendum To The microATX Motherboard
Interface Specification Version 1.2. It will focus on the electrical, mechanical and
thermal interfaces between a Sandy Bridge/Ivy Bridge or Cedar Trail based Thin Mini-
ITX motherboard, and its enclosure and peripherals
Compliance with the guidance outlined in this document enables chassis and Thin
Mini-ITX motherboards that can be interchangeably used between systems. This
increases the system design options using a building block approach, while mitigating
the need for custom solutions.
Revision 1.2 of this document Design Guide includes changes that are intended to
improve the interoperability and system integration experience based on the thin mini
ITX motherboard standard. When designing a chassis based on this revision of the
design guide, a chassis manufacturer should take into consideration whether to
accommodate motherboards in production prior to this document revision.
Motherboard designs based on revision 1.0 of this document are generally expected to
be compatible with Chassis designs based on later revisions, however issues could
include cable length mismatch due to tightening of the connector placement zones in
revision 1.1. Refer to the Channel AIO (Thin Mini-ITX Form Factor) –Compatibility
Matrix for Revision 1.0 based motherboards.
1.2 Overview
Thin Mini-ITX motherboards evolve the standard Mini-ITX form factor in to even
smaller system designs. They are especially useful in segments that place a premium
on small, slim chassis. Typical usages of such chassis are:
All In One (AIO) PCs
Stackable home theater PC to be size compatible with the standard width of AV
components such as DVD players and receivers
VESA mountable Thin PC
Digital signage PC (Built inside or behind a TV or other display)
In this design guide, particular attention is given to slim, sub-4 liter Tiny PCs, and All
In One PCs.

Introduction
Thin Mini-ITX Based PC System Design Guide 9
Figure 1-1. Thin Mini-ITX Applications
1.2.1 All In One PCs
The business model for AIO that works for system integrators is when they can buy
inter-changeable components and design their own custom system configurations, just
like the white box desktop business model.
For this business model to work the following building blocks will be sourced
separately:
AIO Enclosure or Chassis Kit (includes flat panel display, AIO metal and plastics of the
chassis, power adapter and thermal solution if custom)
Motherboard will ship with low profile IO shield, cables to power the HDD and ODD
Other standard components: CPU, Memory, HDD, ODD
All In One PCs which tightly integrate a flat panel display with PC components have
traditionally been based on custom motherboard and chassis designs. Leveraging the
common interfaces in this design guide enables a building block approach to AIO
systems. Common design features on Thin Mini-ITX based AIO PCs can include the
following:

Introduction
10 Thin Mini-ITX Based PC System Design Guide
Table 1-1. Common AIO Features in Thin Mini-ITX Based AIO PCs
Feature
Detailed Description –Guide assumption
18.5” or larger, 16:9, thin, low
power flat panel
LED backlight, goal < 15mm thickness, LVDS
Thin Mini-ITX Motherboard
Motherboard compliant to the Thin Mini-ITX spec standards
in the Mini-ITX Addendum Version 2.0 To the microATX
Motherboard Interface Specification Version 1.2
Audio speakers
4 Ohm speakers capable of supporting 3W
Qty 1, ODD
Thin profile 5.25” ODD, SATA
3.5 or 2.5” SATA, SSD or HDD
Enclosure may support one or two HDD or SSD
Wireless LAN
Mini-PCIe half card
Bluetooth optional
Assume USB Bluetooth module –with antenna on module
or support for discrete antenna
Walkup I/O ports
Options that may be designed in to the chassis include
USB, microphone, headphone ports, and SD card reader.
No specific configurations are defined in this guide.
Buttons / LEDs
On/off, Power on/off LED, Screen brightness switch
System may be supported by the main Thin Mini-ITX motherboard, daughter boards,
and discrete devices.
Daughter boards would be required to support walkup I/O, backlight inverter/driver,
and front panel interface.
Discrete devices with direct cable attach could include the flat panel, HDD, ODD,
camera, touchscreen, IR receiver, IR emitter, right/left speakers, digital microphone,
CPU fan, and system fans.
1.2.2 Tiny PCs
The Mini-ITX form factor enabled chassis down to the 4 –8 liter range. Standard
chassis built around Thin Mini-ITX motherboards may shrink to below 4 liters, creating
a “Tiny PC” category. Tiny PCs include slimmer designs that make especially good use
of the lower height inherent to Thin Mini-ITX motherboards. Figure 1-2 shows a
comparison between current mini-ITX vs. Thin Mini-ITX motherboard thickness
characteristics.

Introduction
Thin Mini-ITX Based PC System Design Guide 11
Figure 1-2. Mini-ITX (left) vs Thin Mini-ITX (right)
1.3 Terminology
Table 1-2. Terms and Descriptions
Term
Description
AIO
All In One
FSC
Fan Speed Control
KIZ
Keep In Zone
KOZ
Keep Out Zone
SFF
8-19 liter chassis (IDC definition)
Tiny PC
Sub-4 liter chassis
Ultra SFF (uSFF)
4-8 liter chassis (IDC definition)

Introduction
12 Thin Mini-ITX Based PC System Design Guide
1.4 Reference Documents
Table 1-3. Reference Documents
Document
Document
No./Location
Mini-ITX Addendum Version 2.0 To the
microATX Motherboard Interface Specification
Version 1.2
www.formfactors.org
ATX Specification Version 2.2
www.formfactors.org
Thermally Advantaged Small Chassis (TASC)
Design Guide
www.formfactors.org
4-Wire Pulse Width Modulation (PWM)
Controlled Fans Specification
www.formfactors.org
ECMA-74 - Measurement of Airborne Noise
emitted by Information Technology and
Telecommunications Equipment
www.ecma-
international.org/publications/standards/Ecma
-074.htm
2nd Generation Intel® Core™ Processor and
LGA1155 Socket Thermal Mechanical
Specifications and Design Guidelines (TMSDG)
324644
VESA eDP
www.displayport.org
www.vesa.org
VESA standard mounting
www.vesa.org/Standards/summary/2006_2.h
tm
Standard Panel Working Group, Rev 3.5
www.spwg.org/specifications.htm
PC form factors web site
www.formfactors.org/developer/specs
Channel AIO (Thin Mini-ITX Form Factor) –
Compatibility Matrix
www.intel.com/go/AIO
Wi-Fi Multi-Band Antenna Integration for
Intel® Processor-based Desktops and All-in-
One Systems
491058
Document numbers and locations are subject to revision and may change.

Thin Mini-ITX Internal Electrical Interfaces
Thin Mini-ITX Based PC System Design Guide 13
2Thin Mini-ITX Internal
Electrical Interfaces
2.1 Common Connector List
A high level goal of this document is to enable interchangeability of chassis with
motherboards from different suppliers. A common set of minimum interface
connectors between the motherboard and chassis is required to achieve a true
building block model for system integrators. The below table outlines these
standardized connectors.
Table 2-1. Internal Motherboard Connectors
Internal Connectors
LVDS
Flat Panel Display Brightness
Front Panel Audio
Internal Stereo Speakers
Digital Microphone (Optional)
SATA
Internal USB
Front Flat Panel
Fans
Consumer Infrared Receiver (Optional)
It is expected that a group of motherboard connectors will exit the system via the Thin
Mini-ITX I/O aperture per industry standards. An example set of external I/O that
could be found on a Thin Mini-ITX motherboard is:
DC Input
USB 2.0
USB 3.0
RJ-45 LAN
HDMI (in/out)
eSATA

Thin Mini-ITX Internal Electrical Interfaces
14 Thin Mini-ITX Based PC System Design Guide
DVI-I
Audio (A/D Line In/Out)
All connector types referenced with a specific manufacturer and model may be
substituted with equivalent, compatible designs. No use of a specific manufacturer is
implied.
Refer to Chapter 5 for recommended internal motherboard header locations and size
considerations.
2.2 Flat Panel Display
Depending on flat panel size, display resolutions, and cost, the flat panel interface
connectivity will vary. For most typical panel resolutions up to and including
1920x1200 a connector that supports the best flat panel performance for LVDS is
defined. The LVDS Flat Panel must be designed for operation at 5V. The system
integrator can then use cabling to adapt the motherboard to any flat panel from basic
single-channel LVDS to dual-channel LVDS at up to 24bpp. The Thin Mini-ITX board
supports the internal display connectors outlined in the section. The display signal
cables must ship as part of the chassis kit.
For flat panel resolutions greater than 1920x1200, eDP is defined. eDP is not a
required interface as of this document revision, however shall the board vendor wish
to provide eDP support as a value-add it must be implemented per the requirements
listed in Section 2.2.2. Please consult with Intel for implementation guidance.
Note that supported graphics resolutions vary between Sandy Bridge/Ivy Bridge, and
Cedar Trail SKUs. Consult the latest processor specifications for supported
resolutions.
2.2.1 LVDS
An internal 40-pin connector for flat panel display and backlight connectivity is
required. Design must support up to the maximum resolution and color depth allowed
by the graphics processor.
40-pin LVDS connector: 1x40, 1A rating per pin, white (reference part number: ACES*
88341-40 or equivalent)
Mating plug reference part numbers: (ACES 88441-40, Starconn* 107F40, or
equivalent)

Thin Mini-ITX Internal Electrical Interfaces
Thin Mini-ITX Based PC System Design Guide 15
Figure 2-1. 40-pin LVDS Header
Table 2-2. 40-pin LVDS Header Pin-Out
Pin
Signal Name
Pin
Signal
1
ODD_Lane3_P
21
N/C
2
ODD_Lane3_N
22
EDID_3.3V
3
ODD_Lane2_P
23
LCD_GND
4
ODD_Lane2_N
24
LCD_GND
5
ODD_Lane1_P
25
LCD_GND
6
ODD_Lane1_N
26
ODD_CLK_P
7
ODD_Lane0_P
27
ODD_CLK_N
8
ODD_Lane0_N
28
BKLT_GND
9
EVEN_Lane3_P
29
BKLT_GND
10
EVEN_Lane3_N
30
BKLT_GND
11
EVEN_Lane2_P
31
EDID_CLK
12
EVEN_Lane2_N
32
BKLT_ENABLE
13
EVEN_Lane1_P
33
BKLT_PWM_DIM
14
EVEN_Lane1_N
34
EVEN_CLK_P
15
EVEN_Lane0_P
35
EVEN_CLK_N
16
EVEN_Lane0_N
36
BKLT_PWR
17
EDID_GND
37
BKLT_PWR
18
LCD_VCC
38
BKLT_PWR
19
LCD_VCC
39
N/C

Thin Mini-ITX Internal Electrical Interfaces
16 Thin Mini-ITX Based PC System Design Guide
Pin
Signal Name
Pin
Signal
20
LCD_VCC
40
EDID_DATA
Note: Motherboard Requirements for Flat Panel Display:
Flat panel display support must be implemented using the defined LVDS
interface for screen resolutions up to and including 1920x1200.
LVDS implementation must support single-channel and dual-channel interface
widths, 18-bpp and 24-bpp color depths, VESA and JEIDA color mappings, and
configurable display timings. Board must have a mechanism for choosing
between such settings and furthermore apply different EDID (or at a
minimum, 18-byte DTD) panel-specific timings to accommodate diverse panel
selection from all chassis vendors.
Motherboard must provide mechanism for adjusting inverter/driver board
settings, namely: maximum PWM, minimum PWM, frequency and polarity.
Intel will maintain a list of panel and inverter/driver board specifications as
registered by chassis vendors (to be available separately).
Motherboard must also provide 5V power to flat panel display and 19V power
to inverter/driver board, each at up to 3A current rating.
AiO Chassis Requirements for Flat Panel Display:
Flat panel displays with a screen resolution up to (and including) 1920x1200
must be LVDS-based. Chassis vendor is responsible for providing panel-
specific datasheet, panel-specific timing information (128-byte EDID data, or
at a minimum 18-byte DTD structure) and inverter/driver board datasheet to
Intel as early as possible for Intel to confirm (and if necessary, disseminate
across board vendors) the necessary display support.
Flat panel display must operate at 5V input voltage. Please also consult with
Intel shall the panel input voltage requirement be different than 5V (for
market assessment purposes only).
Inverter/driver board must operate at 19V input voltage and be matched to
the target panel backlight unit (BLU) specifications so that:
maximum inverter/driver board current output (when driven at 100%
PWM) does not exceed the BLU’s current input tolerance,
and minimum inverter/driver board current output remains within the
BLU’s specification while still producing a legible screen output.
Failure to ensure matching inverter/driver board-to-panel specifications may
result in shortened display life, hardware failure and/or customer
dissatisfaction.

Thin Mini-ITX Internal Electrical Interfaces
Thin Mini-ITX Based PC System Design Guide 17
2.2.2 eDP (VESA Embedded Display Port™)
For flat panel resolutions greater than 1920x1200, eDP is defined in this section. eDP
is not a required interface as of this document revision, however shall the board
vendor wish to provide eDP support as a value-add it must be implemented per the
requirements listed below. Please consult with Intel for further implementation
guidance.
An internal 40-pin eDP panel and backlight connector for four-lane, 2.7Gbps and
1.62Gbps eDP flat panel display support is optional. The design must support up to
maximum resolution and color depth allowed by the graphics processor. The design
must be Embedded Display PortTM (eDP) v1.1a compliant and support hot-plug detect
as well as Direct Drive Monitor (DDM, to allow use of large/AIO panels)
The 40-pin eDP connector must be vertical, single-row shrouded colored black, as
shown in the below figure. Connector must support four lanes of eDP traffic, AUX
channel, panel logic power as well as backlight power and control signals, compliant
with the VESA Embedded Display Port™ (eDP) Standard for 40-pin eDP pin
assignment, as defined in the below table.
40-pin eDP connector: 1x40, 1A rating per pin, black (reference part number: ACES
50203-040)
Mating plug reference part number: ACES 88441-40
Figure 2-2. 40-pin eDP MB Header

Thin Mini-ITX Internal Electrical Interfaces
18 Thin Mini-ITX Based PC System Design Guide
Table 2-3. 40-pin eDP Header Pin-Out
Pin
Signal Name
Pin
Signal
1
NC_Reserved
21
LCD_VCC (3.3V/5V/12V)
2
High-speed_GND
22
LCD_Self_Test-or-NC
3
Lane3_N (DDPD_[3]N)
23
LCD_GND
4
Lane3_P (DDPD_[3]P)
24
LCD_GND
5
High-speed_GND
25
LCD_GND
6
Lane2_N (DDPD_[2]N)
26
LCD_GND
7
Lane2_P (DDPD_[2]P)
27
HPD (DDPD_HPD)
8
High-speed_GND
28
BKLT_GND
9
Lane1_N (DDPD_[1]N)
29
BKLT_GND
10
Lane1_P (DDPD_[1]P)
30
BKLT_GND
11
High-speed_GND
31
BKLT_GND
12
Lane0_N (DDPD_[0]N)
32
BKLT_ENABLE
13
Lane0_P (DDPD_[0]P)
33
BKLT_PWM_DIM
14
High-speed_GND
34
NC_Reserved
15
AUX_CH_P (DDPD_AUXP)
35
NC_Reserved
16
AUX_CH_N (DDPD_AUXN)
36
BKLT_PWR (12V/19V)
17
High-speed_GND
37
BKLT_PWR (12V/19V)
18
LCD_VCC (3.3V/5V/12V)
38
BKLT_PWR (12V/19V)
19
LCD_VCC (3.3V/5V/12V)
39
BKLT_PWR (12V/19V)
20
LCD_VCC (3.3V/5V/12V)
40
NC_Reserved

Thin Mini-ITX Internal Electrical Interfaces
Thin Mini-ITX Based PC System Design Guide 19
2.2.3 Flat Panel Display Brightness
The motherboard must provide an additional connector for powering the inverter or
driver board. An 8-pin FPD_Brightness connector must be 1x8 shrouded, 2.00mm
pitch with 2A rating per pin as shown in the below figure. The connector must also
provide backlight enable and control signals, as well as input pins for brightness
up/down front panel button control signals. The 8-pin FPD Brightness connector must
be validated to support maximum power delivery at 19 Volts, as well as to correctly
support backlight enable/control and brightness up/down signals.
An assortment of LVDS flat panels with CCFL and LED backlights should be used for
validating backlight power and control features.
Backlight brightness must be dynamically controlled via discrete flat panel
brightness buttons.
Figure 2-3. PC & Software Brightness Control:
Figure 2-4. FPD Brightness Header
Table 2-4. 8-pin FPD Brightness Header Pin-Out
Pin
Signal Name
Description
1
BKLT_EN
Backlight enable
2
BKLT_PWM
Backlight control
3
BKLT_PWR
Backlight inverter power

Thin Mini-ITX Internal Electrical Interfaces
20 Thin Mini-ITX Based PC System Design Guide
Pin
Signal Name
Description
4
BKLT_PWR
Backlight inverter power
5
BKLT_GND/Brightness_GND
Ground (shared)
6
BKLT_GND/Brightness_GND
Ground (shared)
7
Brightness_Up
Flat panel brightness increase
8
Brightness_Down
Flat panel brightness decrease
2.2.4 On Screen Display (OSD)
Windows provides built-in support for controlling as well as tracking the display
brightness level within its Power Options control panel. The motherboard BIOS must
be designed to have such control panel control as well as the ability to reflect the
brightness status of the display. It is recommended that an OSD status utility be
available by the motherboard vendor so that a status bar may be shown whenever the
brightness increase/decrease buttons are pressed.