National Semiconductor LMX9838 Bluetooth™ serial dongle reference design ki t is a plug and play serial a dap ter for
serial cable replacement applications and more. It is able
to support more profiles than just the Serial Port Profile
(including audio support with external codec boards). By
using the enclosed Simply Blue Commander software, it
allows user to develop their own SW applications easily
given the built in interpreter for HEX commands. SBSmart
is a higher level application tool that provides buttons with
the built in commands to easily set up or demonstrate different profile support using the Simply Blue SPP package.
2.0General Description
2.1REFERENCE DESIGN KIT CONTENTS
■ LMX9838 Bluetooth serial adapter reference board
■ USB Dongle and application software stack
■ Null modem cabl e
■ Sedona Lite board (Audio CODEC Board)
■ 110V to 240V AC to 5V DC power adapter and pigtail
■ CDROM with design documents and Simply Blue soft-
ware Application tools.
2.2LMX9838 BLUETOOTH SERIAL
ADAPTER REFERENCE BOARD
Figure 1. Reference Board and Sedona Lite Board
Bluetooth is a trademark of Bluetooth SIG, Inc. and is used under license by National Semiconductor.
■ FCC compliance (see Section 13.0): The device com-
plies with Part 15 of FCC Rules. Operation is subject to
the following two conditions:
— This device may not ca use harmful interference
— This device must accept any interference received,
including interference that may cause undesired
operation
■ IC certified:
— IC: 1520A-LMX9838
■ Bluetooth SIG QD ID: B012394
4.0Requirement and Setup
4.1BASIC REQUIREMENT
LMX9838DONGLE Hardware User Guide
■ X86 PC with serial port.
■ One of the following operating system is required.
— Windows 2000
—Windows XP
4.2APPLICATION SOFTWARE
4.2.1Simply Blue Commander
Applicatio n com man d or ien ted t ool to ge ner ate comm ands
and watch events in the Simply Blue Command interface
window. Reference the Simply Blue Commander User
Guide document for details.
4.2.2SBSmart
Easy to use Windows based tool to demonstrate additional
profile support of the Simply Blue functionality. Reference
the SBSmart User Guide for additional details.
4.2.3Patch Programming
LMX9838 allows for patch programming for firmware
update if necessary. Reference the LMX9838 SW User
Guide document for details. This can also be done with the
Simply Blue Commander and SBSmart tools.
Figure 2. System Block Diagram
5.0Functional Description
5.1POWER SUPPLY
■ DC Power Jack (6V max)
■ Battery Holder (6V max)
5.2MAIN SYSTEM
■ Reset button for manual Reset
■ Jumper option for Baud rate selection
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5.3UART INTERFACE
DB9 connector for RS232 standard PC interface using Onboard level shifter IC for handling LMX9838 module’s 3.3V
UART interface.
5.4ADVANCE AUDIO INTERFACE
■ Support Audio applications
■ PCM codec interface (support linear and A-law)
■ PCM Master or Slave operation (SW configurable)
■ Direct connection to Sedona Lite Board (A-law only)
LMX9838DONGLE Hardware User Guide
6.0Design Consideration
6.1POWER MANAGEMENT
■ 3.3V output single LDO is used to provide power for
RS232 interface chi p and Digital porti on of the LMX983 8.
7.0Layout Consideration
The LMX9838 reference design is split into 2 sections, one
section is RS232 transceiver circuit for PC connection,
another section is LMX9838 main circuit for Host processor. (Fig ure 3)
7.1PCB REQUIREMENT
■ 2 layers PCB required
■ 1 mm overall thickness
7.2LAYERS CLASSIFICATION
■ Top layer is the components and main signals layer
■ Bottom layer is interface signals and ground plane
■ RF circuit requirement
■ Large ground plane with ground via’s is must for good
RF performance
8.0AUDIO CODEC Board
Table 2 Connectors Summary
ConnectorDescriptionDetails
J7Battery Connector
2mm pitch
J6DC jackSame as above
J8DP9 serial connec-
tor (male)
J5External processor
interface
J4Advance Audio
interface
Table 3 Jumper and Test Point Summary
Jumper /
Test Point
J1, J2 and J3Clock & UART set-
DescriptionDetails
ting jumper
Maximum input voltage is 6V
See Table 5
See Table 6
See Table 7
See Table 8
Table 4 Switch and LEDs
Switch/LEDDescription
S1Reset button
D1Operation Status
D2Data Traffic (TX/RX)
Sedona Lite Board c on t ai ns an audio codec a nd two phone
jacks. This board can be used in conjuction with
LMX9838DONGLE to realize the audio (SCO) transmission and reception capabilities. (See Table 9)
9.0Board components and Pin Assignments
A summary of t he configuration and se lection jumpers is
provided in the tables that follow. Reference both the schematic and PCB layout (included on the CD in the kit)
Table 1 Major Components List
DeviceDescription
National LMX9838 Serial Port Module - Refer-
U1
ence the device datasheet.
National LP3985 Low-Dropout Voltage Regula-
U3
tor
Maxim MAX3225 1 Mbps High Speed UART
U2
Driver
Table 5 J8 DP9 (male) Pin Assignments
Pin #Signal nameDescription
1NCNo connection
2RxDReceive Data (inp ut)
3TxDTransmit Data (output)
4NCNo connection
5GNDGround
6NCNo connection
7RTSReady to send (output)
8CTSClear to send (input)
9NCNo connection
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Table 6 J5 External Processor Interface
Table 8 UART interface setting
Pin # Signal nameDescription
1POWER_D#ON/OFF control of LMX9838
2VCCLDO output (3.3V)
3GNDGround
4TXDTransmit Data (output)
5CTS#Clear to send (input)
6RXDReceive Data (input)
7RTS#Ready to send (output)
8VCC_CORE
■ LMX9838 Blu etooth Serial Port Module - Sof tware Users
Guide
■ SBSmart user guide
Figure 4. Sedona Board
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13.0Appendix: FCC instructions
13.1SAFETY INFORMATION FOR RF
EXPOSURE
13.1.1FCC Radiation Exposure Statement:
This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. End users
must follow the specific operating instructions for satisfying
RF exposure complia nc e.
This device is intended only form OEM integrators under
the following conditions:
1. The anten na must be installed su ch that 20c m is main-
tained between the antenna and users;
and
2. The transmitter module may not be co-located with any
other transmitter or antenna.
IMPORTANT NOTE: In the event that these conditions can
not be met (for examp le ce rtain laptop con fig urat ion s or c olocation with another transmitter), then the FCC authorization is no longer considered valid and the FCC ID can not
be used on the final product. In these circumstances, the
OEM integrator will be responsible for re-evaluating the
end product (includ ing th e transmitter) and obtaining a separate FCC authorization.
13.1.2End Product Labeling
This transmitter module is authorized only for use in
devices where the antenna may be installed such that 20
cm may be maintained between the antenna and users.
The final end product must be labeled in visible area with
the following:
“Contains TX FCC ID: ED9LMX9838”
13.1.3End Product Manual Information
LMX9838DONGLE Hardware User Guide
rect the interference by one or more of the following measures:
■ Reorient or relocate the receiving antenna.
■ Increase the separation between the equipment and re-
ceiver.
■ Connect the equipment i nto an outlet of a c ircuit different
from that to which the receiver is connected.
■ Consult the dealer or an experienced radio/TV technician for assistance.
Changes or modification not expressly approved by the
party responsible for Compliance could void the user’s
authority to operate the equipment. Connecting of peripherals requires the use of grounded shielded signal cables.
13.2.2FCC Compliance Information
This device complies with Part 15 of FCC Rules.
Operation is subject to the following two conditions:
1) This device may not cause harmful interference, and
2) This device must accept any interference received,
including interference that may cause undesired operation.
The user manual for end users must include the following
information in a prominent location:
“IMPORTANT NOTE:
To comply with FCC RF exposure compliance require-
ments, the antenna used for this transmitter must be
installed to provide a s eparation distance of a t least 20 cm
from all persons and mus t no t be c o-l oc ated or op erat ing in
conjunction with any other ante nna or transm itte r.”
13.2RADIO FREQUENCY INTERFERENCE
STATEMENT
13.2.1INFORMATION TO THE USER
NOTE : This equipm en t h as been tested and fou nd to comply with the limits for a Class B digital device pursuant to
Part 15 of the FCC Rules.
These limits are designed to provide reasonable protection
against harmful Interference in a residential installation
This equipment generates, uses, and can radiate radio frequency energy and, i f Not inst a lled and used in accord ance
with the instructions, may cause harmful Interference to
radio communicati ons . H owe ver, th ere i s n o g uara nte e th at
interference will not occur in a particular Installation. If this
equipment does caus e harm ful int erferenc e to rad io or television reception, which can be determined by turning the
equipment off and on, the user is encouraged to try to cor-
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LMX9838DONGLE Designer Guide
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or systems which,
(a) are intended for surgical implant into the body, or (b) support
or sustain life, and whose failure to perform, when properly used
in accordance with instructions for use provided in the labeling,
can be reasonably expected to result in a significant injury to the
user.
2. A critical component is any component of a life support device
or system whose failure to perform can be reasonably expected
to cause the failure of the life support device or system, or to affect its safety or effectiveness.
BANNED SUBSTANCE COMPLIANCE
National Semiconductor certifies that the products and packing materi als meet the provisions of the Customer Products Stewardship
Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no “Banned
Substances” as defined in CSP-9-111S2.
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
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