SA.3Xm Rubidium Frequency Standard. Designer s Reference Guide Revision C March 2009 Part Number

Transcription

1 SA.3Xm Rubidium Frequency Standard Designer s Reference Guide Revision C March 2009 Part Number

2 Symmetricom, Inc Orchard Parkway San Jose, CA U.S.A. Copyright 2009 Symmetricom, Inc. All rights reserved. Printed in U.S.A. All product names, service marks, trademarks, and registered trademarks used in this document are the property of their respective owners.

3 Contents How to Use This Guide Purpose of This Guide Who Should Read This Guide What s New In This Guide Structure of This Guide Conventions Used in This Guide Warnings, Cautions, Recommendations, and Notes Related Documents and Information Where to Find Answers to Product and Document Questions Chapter 1 Description Overview Description Dimensions Chapter 2 Design Integration Considerations Thermal Considerations Thermal Tape Electrical Interface RF Output BIST (Lock) Signal Frequency Control Calibrate Frequency Discipline Frequency Analog Frequency Input Power RS232 and Communications Basics Communication Protocol Commands EMI and Noise Considerations Chapter 3 Installation and Operation Start-up Sequence Revision C March, 2009 SA.3Xm Designer s Reference Guide 3

4 Table of Contents Reliability and Maintenance SA.3Xm Reliability User Maintenance and Adjustments Troubleshooting Technical Support Appendix A Contents of the Developer s Kit Introduction PCB and Power Supply Base/Heat Sink SA.3Xm Designer s Reference Guide Revision C March, 2009

5 Figures 1-1 SA.3Xm Rubidium Frequency Standard SA.3Xm Dimensions Sequence of Start-up Events A-1 SA.3Xm Developer s Kit A-2 SA.3Xm Schematic Diagram A-3 PCB Assembly A-4 Base/Heat Sink for the SA.3Xm Developer s Kit A-5 Thermal Pad for the SA.3Xm Developer s Kit Revision C March, 2009 SA.3Xm Designer s Reference Guide 5

6 List of Figures 6 SA.3Xm Designer s Reference Guide Revision C March, 2009

7 How to Use This Guide This section describes the format, layout, and purpose of this guide. In This Preface Purpose of This Guide Who Should Read This Guide What s New In This Guide Conventions Used in This Guide Warnings, Cautions, Recommendations, and Notes Related Documents and Information Where to Find Answers to Product and Document Questions What s New In This Guide Purpose of This Guide The SA.3Xm Designer s Reference Guide provides basic recommendations for designing products to use Symmetricom s SA.3Xm Rubidium Frequency Standard. The guidelines in this user guide are generic because specific product requirements vary from application to application. This material consists of a brief description of SA.3Xm design supported by block diagrams, description of environmental issues, installation guidelines, and unit operation. Who Should Read This Guide This document is intended for engineers and telecommunications professionals who are designing, installing, operating or maintaining time, frequency, and synchronization systems having a requirement for a low profile and highly precise frequency generator. To use this document effectively, you should have a good understanding of digital telecommunications technologies and analog frequency generation and synthesis techniques Revision C March, 2009 SA.3Xm Designer s Reference Guide 7

8 How to Use This Guide What s New In This Guide What s New In This Guide This section describes the revision history of this reference guide with the latest updates at the top of the table. Revision Date Notes A June 2008 Initial release. B November 2008 Updates to List of Command (Chapter 2) Minor updates to the reference guide Structure of This Guide This guide contains the following sections: Chapter, Title Chapter 1, Description Chapter 2, Design Integration Considerations Chapter 3, Installation and Operation Appendix A, Contents of the Developer s Kit Description This chapter contains a description of the SA.3Xm and lists its typical applications. It provides information on dimensions, performance, and connector pinouts. This chapter contains mechanical issues pertaining to SA.3Xm mounting recommendations, including thermal and EMI considerations, and frequency control. This chapter contains the information necessary to properly install and operate the SA.3Xm unit. This appendix describes the SA.3Xm Developer s Kit hardware. 8 SA.3Xm Designer s Reference Guide Revision C March, 2009

9 How to Use This Guide Conventions Used in This Guide Conventions Used in This Guide This guide uses the following conventions: Acronyms and Abbreviations Terms are spelled out the first time they appear in text. Thereafter, only the acronym or abbreviation is used. Revision Control The title page lists the printing date and versions of the product this guide describes. Typographical Conventions This guide uses the typographical conventions described in the table below. When text appears this way... TimeProvider User s Guide LOCK Press Enter FC mode enabled r>w r>a Lock-in Symmetricom does not recommend... The title of a document.... it means: An operating mode, alarm state, status, or chassis label. A named keyboard key. The key name is shown as it appears on the keyboard. An explanation of the key s acronym or function immediately follows the first reference to the key, if required. Text in a source file or a system prompt or other text that appears on a screen. A command you enter at a system prompt or text you enter in response to a program prompt. You must enter commands for case-sensitive operating systems exactly as shown. A word or term being emphasized. A word or term given special emphasis Revision C March, 2009 SA.3Xm Designer s Reference Guide 9

10 How to Use This Guide Warnings, Cautions, Recommendations, and Notes Warnings, Cautions, Recommendations, and Notes Warnings, Cautions, Recommendations, and Notes attract attention to essential or critical information in this guide. The types of information included in each are explained in the following examples. Warning: To avoid serious personal injury or death, do not disregard warnings. All warnings use this symbol. Warnings are installation, operation, or maintenance procedures, practices, or statements, that if not strictly observed, may result in serious personal injury or even death. Caution: To avoid personal injury, do not disregard cautions. All cautions use this symbol. Cautions are installation, operation, or maintenance procedures, practices, conditions, or statements, that if not strictly observed, may result in damage to, or destruction of, the equipment. Cautions are also used to indicate a long-term health hazard. ESD Caution: To avoid personal injury and electrostatic discharge (ESD) damage to equipment, do not disregard ESD cautions. All ESD cautions use this symbol. ESD cautions are installation, operation, or maintenance procedures, practices, conditions, or statements that if not strictly observed, may result in possible personal injury, electrostatic discharge damage to, or destruction of, static-sensitive components of the equipment. Electrical Shock Caution: To avoid electrical shock and possible personal injury, do not disregard electrical shock cautions. All electrical shock cautions use this symbol. Electrical shock cautions are practices, procedures, or statements, that if not strictly observed, may result in possible personal injury, electrical shock damage to, or destruction of components of the equipment. Recommendation: All recommendations use this symbol. Recommendations indicate manufacturer-tested methods or known functionality. Recommendations contain installation, operation, or maintenance procedures, practices, conditions, or statements, that provide important information for optimum performance results. Note: All notes use this symbol. Notes contain installation, operation, or maintenance procedures, practices, conditions, or statements, that alert you to important information, which may make your task easier or increase your understanding. 10 SA.3Xm Designer s Reference Guide Revision C March, 2009

11 How to Use This Guide Related Documents and Information Related Documents and Information See your Symmetricom representative or sales office for a complete list of available documentation. Note: Symmetricom offers training courses designed to enhance your knowledge of the SA.3Xm Rubidium Frequency Standard. Contact your local representative or sales office for a complete list of courses and outlines. Where to Find Answers to Product and Document Questions For additional information about the products described in this guide, please contact your Symmetricom representative or your local sales office. You can also contact us on the web at Revision C March, 2009 SA.3Xm Designer s Reference Guide 11

12 How to Use This Guide Where to Find Answers to Product and Document Questions 12 SA.3Xm Designer s Reference Guide Revision C March, 2009

13 Chapter 1 Description This section contains a description of the SA.3Xm and its typical applications. It provides information on dimensions, performance, and connector pinouts. In This Chapter Overview Description Dimensions Overview The SA.3Xm is a revolutionary rubidium reference design, and marks a new direction in the industry. This designer's reference guide provides the basic guidelines and recommendations for designing products with the SA.3Xm family of references. These are generic, and should be tailored for each application. This document is intended for engineers, technicians and technologists who are designing, installing, operating or maintaining time, frequency and synchronization systems. The SA.3Xm is a low profile, highly precise frequency generator. To use this document effectively, an understanding of digital (especially digital communication) technologies is required. It is advantageous to have a background in frequency generation and synthesis techniques. For additional information, or to get product updates, please contact the designated Symmetricom representative. You may also contact Symmetricom, Inc. directly via the web site at Revision C March, 2009 SA.3Xm Designer s Reference Guide 13

14 Chapter 1 Description Description Description The SA.3Xm rubidium atomic frequency reference is Symmetricom's sixth generation gas cell atomic oscillator technology product. It reflects significant advances in physics miniaturization and atomic interrogation algorithms which serve to reduce size and power while providing stable reference frequencies which are immune to environmental perturbation. The SA.3Xm comes in several performance levels for application to specific system requirements. The SA.3Xm offers a low height (17.8 mm / 0.70"), a small footprint (50.8 mm X 50.8 mm or 2 in x 2 in), and an industrial operating temperature range of 10 C to +75 C (baseplate temperature). Figure 1-1. SA.3Xm Rubidium Frequency Standard The SA.3Xm design has been refined for cost effective mass production and can be easily integrated into time, frequency and synchronization systems. The SA.3Xm requires a single supply voltage and can be mounted directly onto a circuit board as a component of a module used in 20 mm (0.8") wide card slots. The design produces a stable frequency with good short and long term stability, and excellent spurious performance. This Designer's Guide provides engineering information for use of the SA.3Xm. It also provides supporting information for use of the Developer's Kit. Furthermore, the design details of the developer's kit can be used to assist with host system design (for example, power conditioning, signal buffering, and so on) This Guide should be used in conjunction with the current data sheet for the SA.3Xm, which is available on the Symmetricom web site at 14 SA.3Xm Designer s Reference Guide Revision C March, 2009

15 Chapter 1 Description Dimensions Dimensions Figure 1-2. SA.3Xm Dimensions Revision C March, 2009 SA.3Xm Designer s Reference Guide 15

16 Chapter 1 Description Dimensions Table 1-1. SA.3Xm Pin and Signal Description Pin Description Characteristic / Limit 1 Frequency Control Input Voltage V * 2 Baseplate (connect to GND externally) 0 V 3 ACMOS Output 10.0 MHz, 3.3V ACMOS squarewave * 4 Ground (signal and supply) 0 V 5 Power Input V 6 BIST (Built-In Self Test), indicates status of unit 3.3 V = Unlocked 0 V = Locked 7 RS232 Transmit 3.3 V CMOS from SA.3Xm 8 RS232 Receive 3.3 V CMOS to SA.3Xm * Pins 2 and 4 are not connected internally. 16 SA.3Xm Designer s Reference Guide Revision C March, 2009

17 Chapter 2 Design Integration Considerations This section provides information on mounting and mating connectors, operating temperature, electrical interface, and noise susceptibility. In This Chapter Thermal Considerations Electrical Interface Communication Protocol EMI and Noise Considerations Thermal Considerations Thermal Tape In order to achieve the highest ambient operating temperature for the SA.3Xm, it is recommended that the bottom ( baseplate ) of the SA.3Xm have good thermal contact with the mounting surface. To ensure good thermal contact, Symmetricom recommends that you secure the SA.3Xm using (5) 2-56 screws. The location of the five screw holes is detailed in Figure 1-2. Caution: To avoid damage to the SA.3Xm, the mounting screws must not penetrate the unit by more that 0.07 in (1.8 mm). It is also very important to maintain a uniform temperature into the baseplate of the SA.3Xm through its mounting points. The SA.3Xm unit will operate normally without the use of thermal tape, but for some applications, a conductive thermal pad or tape may simplify customer system thermal design requirements. Warning: To avoid the possibility of a burn, you must mount the SA.3Xm to a heat-dissipating surface. The SA.3Xm operates at a temperature that is hot to the touch and may cause handling distress. As the baseplate temperature continues to increase, the unit will eventually lose lock. Above a baseplate temperature of +75 C, the physics package heater shuts down as control point temperatures are exceeded and the unit temperature coefficients increase Revision C March, 2009 SA.3Xm Designer s Reference Guide 17

18 Chapter 2 Design Integration Considerations Electrical Interface Electrical Interface RF Output 10 MHz 3.3 volt ACMOS square wave Logic Level: VL < 0.5V, VH > 2.7V (15 pf load) Rise / Fail Time: <10ns Duty Cycle: 50% ±10% The RF Output has not been designed to drive a 50 ohm load but is source terminated by 50 ohms to minimize reflections if a relatively long line is used for this signal. BIST (Lock) Signal The SA.3Xm provides an indication that the internal quartz oscillator is locked to the rubidium atomic resonance via the Built In Self Test signal. As long as the BIST signal is low, once warm-up is completed, the user can be assured that the output frequency is locked to the rubidium atomic resonance. The lock status is also available via the RS232 commands c or ^ (see Commands, on page 20). If the BIST signal is high, atomic lock has not been attained or has been lost and the SA.3Xm will enter Sweep Mode to reacquire lock. During the sweep, signal output amplitude is maintained but no reliance should be placed on signal accuracy or stability. Lock acquisition typically takes 5 minutes, but in Parameter Recovery mode, lock acquisition can take 2 hours. Frequency Control The output frequency of the SA.3Xm may be changed in two ways: a digital tuning command may be issued via RS-232 command (preferred) and an analog dc tuning voltage may be applied to Pin 1 (if analog tuning is enabled). It is highly recommended that frequency control be implemented by only one of the two methods. Do not try to combine both approaches into one system. The output frequency of the SA.3Xm is given in the following equation: f output f calibrate f discipline f analog where the different terms represent variables which may be independently controlled by the user. This equation is recalculated based upon current values and applied to the frequency control servo at 100 ms intervals. 18 SA.3Xm Designer s Reference Guide Revision C March, 2009

19 Chapter 2 Design Integration Considerations Electrical Interface Calibrate Frequency The calibrate frequency value is stored in non-volatile memory in the SA.3Xm and is retrieved for active use at startup. The active calibrate frequency may be overwritten (but is not stored to non-volatile memory) with a user command (See Frequency Calibrate, on page 20). The stored calibrate frequency value can be updated with a user command (see Save Frequency Calibrate Value to Non-Volatile Memory, on page 21). Discipline Frequency The discipline frequency value is useful in an application where the SA.3Xm is locked to another reference signal (e.g. to GPS). The discipline frequency is overwritten by new discipline frequency as provided by the user. The discipline frequency value is set to zero at startup. Analog Frequency The analog frequency control is derived from the analog voltage applied to Pin 1. This voltage is digitized, scaled and applied to the SA.3Xm frequency servo as indicated in Equation 1. Analog tuning voltages above mid-point, increase the output frequency and conversely. If the analog frequency tuning is disabled, the analog frequency control value is zero. Specifications for the analog tuning range (frequency range and applicable voltage) are provided on the Data Sheet; the mid-point of the analog tuning (e.g. 2.5 V) provides zero analog frequency control value. Input Power The input power for the SA.3Xm is 5 volts. Detailed specifications for operating ranges are provided in the Product Data Sheet Revision C March, 2009 SA.3Xm Designer s Reference Guide 19

20 Chapter 2 Design Integration Considerations Communication Protocol RS232 and Communications Basics The RS232 RX and TX signals are used to communicate with the SA.3Xm for the purpose of controlling and monitoring. The characteristics of both RX and TX are: 3.3V = ACMOS 3.3V = idle state 0V = active state The data rate and word structure are: 57,600 Baud 8 bits character parity none 1 bit Stop Communication Protocol The SA.3Xm communication protocol supports two types of commands: Single keystroke no carriage return is required Multi keystroke requires a specific start (<) and end (>) character. Used for commands that require a payload Commands All digital frequency tuning commands are signed (positive or negative) integers in normalized units of Enable/Disable Analog Tuning Command syntax: A or a Response:...Analog Tuning ENABLED /...Analog Tuning DISABLED Frequency Calibrate Command syntax: <FC+/-ddddd> (where ddddd is in parts of ) Response:...Persistent Frequency Adjustment = +/-ddddd Frequency Discipline Command syntax: <FD+/-ddddd> (where ddddd is in parts of ) Response:...One Time Frequency Adjustment = +/-ddddd 20 SA.3Xm Designer s Reference Guide Revision C March, 2009

21 Chapter 2 Design Integration Considerations Communication Protocol Save Frequency Calibrate Value to Non-Volatile Memory Command syntax: <FS> Response:...Saving... DDS Center Frequency to Flash Display Current Values Command syntax: c Response: See Table 2-1 BITE 0 1 Built-in Self Test (0 = Locked) Firmware Version xxx SerialNumber YYMMMCXXXXX TEC Control (mdegc) xxxxx RF Control (0.1mv) xxxxx DDS Frequency Center Current (0.01Hz) xxxxxxxxx CellHeaterCurrent (ma) xxx DCSignal (mv) xxxx Temperature (mdegc) xxxxx Digital Tuning (0.01Hz) 0 1 Analog Tuning On/Off 0 1 (0 = Inactive) Analog Tuning (mv) xxxxx Command syntax: ^ Response: Comma-delimited string of the above values in the order listed, followed by a carriage return Revision C March, 2009 SA.3Xm Designer s Reference Guide 21

22 Chapter 2 Design Integration Considerations EMI and Noise Considerations Table 2-1. Response for c Command Description Values Comments BITE 0 1 Built-in Self Test 0 = clock locked and functioning 1 = clock not locked Firmware version xxx Serial Number YYMMMCXXXXX Unique for each unit TEC Control (mdegc) RF Control (0.1 mv) DDS Frequency Center Current (0.01 Hz) Cell Heater Current (ma) DC Signal (mv) Temperature (mdegc) Digital Tuning ((0.01 Hz) xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx Analog Tuning On/Off 0 1 Analog tuning pin status 1 = Active, 0 = Inactive Analog Tuning (mv) xxxxx EMI and Noise Considerations The SA.3Xm is designed to comply with applicable FCC requirements if mounted properly to the host PCB. When a user has an application where the phase noise and spur integrity are crucial, the SA.3Xm must be provided with a clean source of dc power (free of spurious current or voltage noise). Connecting fans, heaters, and other switching devices to the dc supply powering the SA.3Xm can result in degraded performance. This noise is coupled through the power line to cause modulation spurs on the output signal. Special care should be taken to avoid noise at 100 Hz and its harmonics (roughly up to the tenth harmonic). If power line filtering is added at the power input pin of the SA.3Xm, this filtering cannot have any resonance points greater than the specified impedance of less than 0.1 ohms from dc to 100 khz in order to avoid the potential for noise peaking or oscillations in the internal power regulators. 22 SA.3Xm Designer s Reference Guide Revision C March, 2009

23 Chapter 2 Design Integration Considerations EMI and Noise Considerations In addition, the input operating voltage range specified for the SA.3Xm during turn-on must continue to be met during operation of the unit. For example, using a 0.3 ohm dc source resistance for the input +5Vdc supply line would not be appropriate since the voltage drop resulting from this resistance (caused by the turn-on current or quiescent operating current) would cause the input voltage to drop below the allowable value Revision C March, 2009 SA.3Xm Designer s Reference Guide 23

24 Chapter 2 Design Integration Considerations EMI and Noise Considerations 24 SA.3Xm Designer s Reference Guide Revision C March, 2009

25 Chapter 3 Installation and Operation This section provides information on details to consider when installing the SA.3Xm and the procedure to follow when turning on the unit. It also contains troubleshooting and customer support information. In This Chapter Start-up Sequence Reliability and Maintenance Technical Support Start-up Sequence Caution: To avoid severe damage to the unit, do not apply power to the incorrect terminals. The SA.3Xm does not have reverse voltage protection. When power is connected to Pin 5, the SA.3Xm unit begins its warm-up cycle. A typical warm-up sequence is shown in Figure 3-1. Note: A signal appears at the output immediately after power is applied to the unit. This output signal is not stable until the oscillator has locked Revision C March, 2009 SA.3Xm Designer s Reference Guide 25

26 Chapter 3 Installation and Operation Reliability and Maintenance Performance of the SA.3Xm unit will vary according to the product version specified at the time of order. Refer to the SA.3Xm product Data Sheet for information on unit performance for the specific product version purchased. Serial Interface Dialog OK Mute Power 14 watts 8 watts 5 watts Quiescent Operation ~ 1 minute ~ 4 minutes BIST CMOS High The BITE signal goes low once the unit has completed its warmup cycle (~5 minutes) ~ 5 minutes Figure 3-1. Sequence of Start-up Events Reliability and Maintenance SA.3Xm Reliability The SA.3Xm is designed for more than ten years of operation without factory adjustment. In order to accomplish this, the major mechanisms impacting the need for maintenance have been addressed including adequate rubidium supply, sufficient adjustment range for the internal quartz oscillator, and sufficient dynamic range of the rubidium resonance control loop. User Maintenance and Adjustments The SA.3Xm is considered to be factory serviceable only. There are no user service adjustments or maintenance required. If the unit fails to operate properly, or has reached the end of its' effective life, contact Symmetricom Global Services for the return/disposal procedure. 26 SA.3Xm Designer s Reference Guide Revision C March, 2009

27 Chapter 3 Installation and Operation Troubleshooting Troubleshooting If, after installation, the SA.3Xm fails to provide signal or communication outputs, or if the unit fails to achieve lock, verify the following: Is the external power supply providing power at the correct voltage at the input power pin? Is the external power supply current at expected levels for the operational mode (e.g. warm-up)? Is there excess humidity or moisture inside the operating area? Is the case temperature below -10 C or above +75 C? The unit will not start properly for temperatures outside this range. Technical Support If you encounter any difficulties installing or operating the product, contact Symmetricom Global Services: U.S.A Call Center (for USA, Canada, Latin America including Caribbean, Pacific Rim including Asia, Australia, and New Zealand) Symmetricom, Inc Orchard Parkway San Jose, CA Toll-free in North America: Telephone: Fax: support@symmetricom.com Europe, Middle East, and Africa (EMEA) Call Center: Symmetricom Global Services EMEA Fichtenstr Hofolding Germany Telephone: Fax: emeasupport@symmetricom.com Internet: Revision C March, 2009 SA.3Xm Designer s Reference Guide 27

28 Chapter 3 Installation and Operation Technical Support 28 SA.3Xm Designer s Reference Guide Revision C March, 2009

29 Appendix A Contents of the Developer s Kit Chapter This appendix provides information on the SA.3Xm Developer s Kit. In This Appendix Introduction PCB and Power Supply Base/Heat Sink Introduction The SA.3Xm Developer's Kit is provided by Symmetricom as a design aid and development tool. It permits a design engineer to experiment with Symmetricom's SA.3Xm product in various applications and to determine how to implement it in the most advantageous manner. Figure A-1 illustrates the Developer s Kit Screws and Washers (Qty 4) Thermal Tape Interface PCB Assembly Base/Heat Sink 2-56 Screws (Qty 5) Figure A-1. SA.3Xm Developer s Kit Revision C March, 2009 SA.3Xm Designer s Reference Guide 29

30 Appendix A Contents of the Developer s Kit Introduction Table A-1. Contents of the Developer s Kit Item Description Interface Printed Circuit Board Assembly Symmetricom Part Number Base/Heat Sink Power Cord Assembly, VAC/15VDC/2A Mounting Hardware (Qty: 4) pan head, 4-40; UNC-2A X 0.25-inch long screws SA.3Xm of chosen performance level (if purchased with kit) CD, Designer's Reference Guide Thermal Tape (Qty: 4) #4, small pattern; 0.25-inch OD flat washers (Qty: 5) pan head, 2-56; UNC-2A X 0.25-inch long screws Screw penetration into the SA.3Xm housing shall not exceed 0.07 in. 30 SA.3Xm Designer s Reference Guide Revision C March, 2009

31 Appendix A Contents of the Developer s Kit PCB and Power Supply PCB and Power Supply The Developer's Kit PCB and power supply consists of: AC to DC 15 volts power supply (external) Sockets to plug in a SA.3Xm A DC/DC Converter (U1) to step down the 15 volts to the 5 volts required by the SA.3Xm 10 MHz CMOS output (J3) 10 MHz SINE output (J6) RS232 connector J5 and RS232 level converter (U3) Analog (0-5V) Tuning Input (J4) BIST Output (J7) The schematic and PCB assembly are shown in Figure A-2 and Figure A-3. Base/Heat Sink The Developer's Kit base/heat sink serves two purposes: 1. It provides a base with standoffs that allow easy use of the Developer's Kit PCB. 2. It serves as a heat sink for the SA.3Xm. Figure A-4 is a drawing of this base/heat sink that can be used as a reference design. Figure A-5 is a drawing with material specification for the thermal pad between the SA.3Xm and the heat sink. The SA.3Xm can also be mounted directly to a PCB depending on the thermal requirements and conditions of the application Revision C March, 2009 SA.3Xm Designer s Reference Guide 31

32 Appendix A Contents of the Developer s Kit Base/Heat Sink Figure A-2. SA.3Xm Schematic Diagram 32 SA.3Xm Designer s Reference Guide Revision C March, 2009

33 Appendix A Contents of the Developer s Kit Base/Heat Sink Figure A-3. PCB Assembly Revision C March, 2009 SA.3Xm Designer s Reference Guide 33

34 Appendix A Contents of the Developer s Kit Base/Heat Sink Figure A-4. Base/Heat Sink for the SA.3Xm Developer s Kit 34 SA.3Xm Designer s Reference Guide Revision C March, 2009

35 Appendix A Contents of the Developer s Kit Base/Heat Sink Figure A-5. Thermal Pad for the SA.3Xm Developer s Kit Revision C March, 2009 SA.3Xm Designer s Reference Guide 35

36 Appendix A Contents of the Developer s Kit Base/Heat Sink 36 SA.3Xm Designer s Reference Guide Revision C March, 2009