WT41U-E-HCI21001 - SILICON LABS

WT41u

DATA SHEET

Wednesday, 25 October

2017 Version 1.1

Silicon Laboratories Finland Oy

VERSION HISTORY

Version Comment

0.8 First version

0.8.1 Table reformatting, value updates etc

0.8.2 Replaced “Bluecore4” with “chipset”, added ordering codes

0.8.3 Rest of table reformatting, added antenna & connector dimension drawings

0.8.4 Added current consumption, RF characteristics

0.8.5 Added certification texts

0.8.6 Added current consumption results, edit TX power variation over VDD range.

0.8.7 Slight edits to specifications

0.8.8 OPN descriptions updated

0.8.9 Bluetooth QDID and Declaration IDs updated

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TABLE OF CONTENTS

1 Ordering Inf ormation......................................................................................................................................6

2 Pinout and Terminal Description ...................................................................................................................7

3 Electrical Characteristics ............................................................................................................................ 11

3.1 Absolute Maximum Ratings ................................................................................................................ 11

3.2 Recommended Operating Conditions ................................................................................................. 11

3.3 Input / Output Terminal Characteristics .............................................................................................. 12

3.3.1 Input/Output Terminal Characteristics (Digital) ............................................................................ 12

3.3.2 Input/Output Terminal Characteristics (USB) .............................................................................. 13

3.4 PIO Current Sink and Source Capability ............................................................................................. 13

3.5 Transmitter Performance For BDR ..................................................................................................... 14

3.6 Recei ver Per f ormance ........................................................................................................................ 15

3.7 Current Consumption .......................................................................................................................... 15

4 Physical Dimensions .................................................................................................................................. 16

5 Layout Guidelines ....................................................................................................................................... 19

6 UART Interface ........................................................................................................................................... 20

6.1 UART Bypass ...................................................................................................................................... 22

6.2 UART Configuration While Reset is Active ......................................................................................... 22

6.3 UART Bypass Mode ............................................................................................................................ 22

7 USB Interface ............................................................................................................................................. 23

7.1 USB Data Connections ....................................................................................................................... 23

7.2 USB Pull-Up resistor ........................................................................................................................... 23

7.3 USB Power Supply .............................................................................................................................. 23

7.4 Self-Powered Mo de ............................................................................................................................. 23

7.5 Bus-Powered Mo de ............................................................................................................................. 24

7.6 USB Suspend Current ......................................................................................................................... 25

7.7 USB Detach and Wake-Up Signaling.................................................................................................. 25

7.8 USB Driver .......................................................................................................................................... 26

7.9 USB v2.0 Compliance and Compatibility ............................................................................................ 26

8 Serial Peripheral Interface (SPI) ................................................................................................................. 27

9 PCM Codec Interface ................................................................................................................................. 28

9.1 PCM Interface Master/Slave ............................................................................................................... 28

9.2 Long Frame Sync ................................................................................................................................ 29

9.3 Short Frame Sync ............................................................................................................................... 29

9.4 Multi-slot Operation ............................................................................................................................. 30

9.5 GCI Interface ....................................................................................................................................... 30

9.6 Slots and Sample Formats .................................................................................................................. 31

9.7 Additional Features ............................................................................................................................. 32

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9.8 PCM_CLK and PCM_SYNC Generation ............................................................................................ 32

9.9 PCM Conf ig urati on .............................................................................................................................. 33

10 I/O Parallel Ports ..................................................................................................................................... 36

10.1 PIO Defaults ................................................................................................................................. 36

11 Reset ....................................................................................................................................................... 37

11.1 Pin States on Reset ..................................................................................................................... 38

12 Certifications ........................................................................................................................................... 39

12.1 Bluetooth ...................................................................................................................................... 39

12.2 FCC .............................................................................................................................................. 39

12.3 ISEDC .......................................................................................................................................... 40

12.3.1 ISEDC (Fra nçais) ......................................................................................................................... 40

12.4 CE ................................................................................................................................................ 41

12.5 MIC Japan .................................................................................................................................... 42

12.6 Qualified Antenna Types for WT41u-E and WT41u-N ................................................................ 43

12.7 Moisture Sensitivity Level (MSL).................................................................................................. 43

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WT41u Bluetooth® Module

DESCRIPTION

WT41u is a long range class 1, Bluetooth® 2.1 +

EDR module. WT41u is a highly integrated and

sophisticated Bluetooth® module, containing all the

necessary elements from Bluetooth® radio and a

fully implemented protocol stack. Therefore, WT41u

provides an ideal solution for developers who want

to integrate Bluetooth® wireless technology into

their design with limited knowledge of Bluetooth®

and RF technologies. WT41u is optimized for long

range applications is available with an integrated

chip antenna, an RF pin for a custom on-board

antenna or a U.FL connector for an external 2dBi

dipole antenna.

By default, WT41u module is equipped with

powerful and easy-to-use iWRAP firmware. iWRAP

enables users to access Bluetooth® functionality

with simple ASCII commands delivered to the

module over serial interface - it's just like a

Bluetooth® modem.

APPLICATIONS:

• Hand held terminals

• Industrial devices

• Point-of-Sale systems

• PCs

• Personal Digital Ass istants (PDAs)

• Computer Accessories

• Access Points

• Automotive Diagnostics Units

FEATURES:

• Fully Qualified Bluetooth v2.1 + EDR end

product

• CE qualified

• Full modular certificat ion for FCC and IC

• MIC Japan compatibility fully tested with ARIB

STD-T66

• TX power: 17 dBm

• RX sensitivity: -94 dBm

• Integrated chip antenna, RF pin or U.FL

antenna connect or

• Class 1, range up to 650 meters with chip

antenna or up to 1km with an ex ter nal dipole

• Industrial temperature range from -40oC to

+85oC

• RoHS Compliant

• USB interfa ce (USB 2.0 co mp atibl e)

• UART with bypass mode

• 6 x GPIO

• 1 x 8-bit AIO

• Integrated iWRAPTM Bluetooth stack or HCI

firmware

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1 Ordering Information

Firmware U.FL Connector Internal chip antenna

iWRAP 5.6 firmware WT41u-E-AI56 WT41u-A-AI56

iWRAP 5.5 firmware WT41u-E-AI55 WT41u-A-AI55

iWRAP 5.0.2 firmware WT41u-E-AI5 WT41u-A-AI5

HCI firmware, BT2.1 + EDR WT41u-E-HCI21 WT41u-A-HCI21

Table 1: Ordering information

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2 Pinout and Terminal Description

Pins 1 and 52 (GND)

are not connected

and have been

removed

GND

RFGND

GND

VDD_PA

PIO2

PIO3

UART_RTS

UART_RX

GND

USB+

USB-

UART_CTS

PCM_IN

PCM_CLK

PCM_SYNC

GND

PCM_OUT

PIO4

GND

VDD

RESET

PIO6

PIO7

GND

SPI_CSB

SPI_CLK

SPI_MISO

SPI_MOSI

PIO5

UART_TX

AIO

Figure 1: WT41u pin out

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Pad name Pad

number Pad type Description

NC 1, 52 Not connected Pins 1 and 52 are not present on the footprint

RESET 33 Digital input Active low reset with weak internal pull-up. Keep

low for >5ms to reset module

GND 2-10, 16, 23,

24, 26-28,

30, 31, 36,

44-49, 53-

Ground Ground pads should all be connected to a ground

plane with minimum trace length, especially on the

antenna end of the module

RF 51 Not connected No internal connection

RFGND 50 Ground Connect to ground plane

VDD_PA 11 Sup pl y voltag e Supply voltage for the RF power amplifier and low

noise am plifier

VDD 32 Suppl y voltage Supply voltage for the Bluetooth chipset

Table 2: Supply and RF Terminal Descriptions

PIO signal Pad number Description

PIO[2] 12 Bi-directional digital in/out with programmable strength and pull-up/pull-

down

PIO[3] 13 Bi-directional digital in/out with programmable strength and pull-up/pull-

down

PIO[4] 29 Bi-directional digital in/out with programmable strength and pull-up/pull-

down

PIO[5] 41 Bi-directional digital in/out with programmable strength and pull-up/pull-

down

PIO[6] 34 Bi-directional digital in/out with programmable strength and pull-up/pull-

down

PIO[7] 35 Bi-directional digital in/out with programmable strength and pull-up/pull-

down

AIO[1] 43 Bi-directional analog in/out

Table 3: GPIO Terminal Descriptions

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PCM signal Pad number Pad type Description

PCM_OUT 25 Output, weak internal pull-down Synchronous data output

PCM_IN 20 Input, weak internal pull-down Synchronous data input

PCM_SYNC 22 Bi-directional, weak internal pull-down Synchronous data sync

PCM_CLK 21 Bi-directional, weak internal pull-down Synchronous data clock

Table 4: PCM Terminal Descriptions

UART signal Pad number Pad type Description

UART_TX 42

Output, weak internal

pull-up UART data output, active

high

UART_RTS# 14

Output, weak internal

pull-up

UART request to send,

active low

UART_RX 15 Input, weak internal pull-

down

UART data input, active

high

UART_CTS# 19 Input, weak internal pull-

down

UART clear to send,

active low

Table 5: UART Terminal Descriptions

USB signal Pad number Pad typ e Description

USB+ 17 Bidirectional USB data line with internal 1.5kohm pull-up

USB- 18 Bidirectional USB data line

Table 6: USB Terminal Description s

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SPI signa l Pad

number Pad type Description

SPI_MOSI 40 Input, weak internal pull-down SPI data input

SPI_CS# 37 Input, weak internal pull-up Chip select, active low

SPI_CLK 38 Input, weak internal pull-down SPI clock

SPI_MISO 39 Output, weak internal pull-down SPI data output

Table 7: Terminal Descriptions

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3 Electrical Characteristics

3.1 Absolute Maximum Ratings

Specification Min Max Unit

Storage temperature -40 85 °C

VDD_PA, VDD -0.4 3.7 V

Other terminal voltages VSS-0.4 VDD+0.4 V

Table 8: Absolute Maximum Ratings

3.2 Recommended Operating Conditions

Specification Min Max Unit

Operating temperature -40 85 °C

VDD_PA, VDD 3.0 3.6 V

Table 9: Recommended Operating Conditions

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3.3 Input / Output Terminal Characteristics

3.3.1 Input/Output Terminal Characteristics (Digital)

Digital Terminals Min Typ Max Unit

Input Voltage Levels

VIL input logic level low 2.7 V ≤ VDD ≤ 3.0 V -0.4 - 0.8 V

1.7 V ≤ VDD ≤ 1.9 V -0.4 - 0.4 V

VIH input logic level high 0.7 VDD - VDD + 0.4 V

Output Voltage Levels

VOL output logic level low

(IO = 4.0 mA) 2.7V ≤ VDD ≤ 3.0 V

- - 0.2 V

VOL output logic level low

(IO = 4.0 mA) 1.7V ≤ VDD ≤ 1.9

- - 0.4 V

VOL output logic level high

(IO = 4.0 mA) 2.7V ≤ VDD ≤ 3.0 VDD - 0.2 - V

VOL output logic level high

(IO = 4.0 mA) 1.7V ≤ VDD ≤ 1.9 VDD - 0.4 - V

Input and Tristate Current with

Strong pull-up -100 -40 -10 µA

Strong pull-down 10 40 100 µA

Weak pull-up -5.0 -1.0 -0.2 µA

Weak pull-down 0.2 1.0 5.0 µA

I/O pad leakage current -1 0 1 µA

CI input capacitance 1.0 - 5.0 pF

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3.3.2 Input/Output Terminal Characteristics (USB)

USB Terminals Min Typ Max Unit

VDD_USB for correct USB operation 3.1 3.6 V

Input Threshold

VIL input logic level log - - 0.3VDD_USB V

VIH input logic level high 0.7VDD_USB - - V

3.4 PIO Current Sink and Source Capability

Figure 2: WT41u PIO Current Drive Capability

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3.5 Transmitter Performance For BDR

RF characteristic Min Typ Max Bluetooth specification Unit

Max transmit power 16 17 18 <20 dBm

Transmit power variation over temperature

range -2 2 dB

Transmit power variation over supply voltage

range -0.5 0.5 dB

Transmit power variation over frequency

range -0.5 0.5 dB

Transmit power control range -13 17 dBm

20dB bandwidth for modulated carrier 998 <1000 kHz

Avg drift -11 6 ±40 kHz

ΔF1avg 165 140 to 175 kHz

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3.6 Receiver Performance

Antenna gain not taken into account

Characteristic, VDD=3.3V, room temperature Packet type Typ Bluetooth

specification Unit

Sensitivity for 0.1% BER

DH1 -94.1 -70 dBm

DH5 -90.5 dBm

2-DH1 -96.5 dBm

2-DH5 -94.5 dBm

3-DH1 -89.5 dBm

3-DH5 -86 dBm

Sensitivity variation over temperature range +/-2 dB

Table 10: Receiver sensitivity

3.7 Current Consumption

Operating m o de Peak Average Unit

Stand-by, page mode 0 2000 1 2 mA

TX 3-DH5 108 85 mA

TX 2-DH5 108 85 mA

TX DH5 184 136 mA

RX 50 44 mA

Deep sleep, page mode 0 2000 1 0.36 mA

Inquiry 113 58 mA

Table 11: Current consumption

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4 Physical Dimensions

Figure 3: Physical dimensions (top view)

Figure 4: Dimensions for the RF pin used as antenna connection on WT41u-N (top view)

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Figure 5: Dimensions of WT41u-E

Figure 6: Dimensions of WT41u-A

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Figure 7: Recommended land pattern

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5 La yout Guidel i n es

Use good layout practices to avoid excessive noise coupling to supply voltage traces or sensitive analog

signal traces, such as analog audio signals. If using overlapping ground planes use stitching vias separated

by max 3 mm to avoid emiss ion from the edges of the PCB. Connect al l the GND pins dir ectly to a solid G ND

plane and m ak e sure that t here is a lo w impedanc e path f or the retur n curren t following t he signa l and sup ply

traces all the way from start to the end.

A good practice is to dedicate one of the inner layers to a solid GND plane and one of the inner layers to

supply voltage planes and traces and route all the signals on top and bottom layers of the PCB. This

arrangement will make sure that any return current follows the forward current as close as possible and any

loops are minimized.

Signals

GND

Power

Signals

Figure 8: Typical 4 -layer PCB construction

Overlapping GND layers without

GND stitching vias Overlapping GND layers with

GND stitching vias shielding the

RF energy

Figure 9: Use of stitching vias to avoid emissions from the edges of the PCB

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6 UART Interface

This is a standard UART interface for communicating with other serial devices.WT41u UART interface

provides a simple mechanism for communicating with other serial devices using the RS232 protocol.

Four signals are used to implement the UART function. When WT41u is connected to another digital device,

UART_RX and UART_TX transfer data between the two devices. The remaining two signals, UART_CTS and

UART_RTS, can be used to implement RS232 hardware flow control where both are active low indicators. All

UART connections are implemented using CMOS technology and have signalling levels of 0V and VDD.

UART configuration parameters, such as data rate and packet format, are set using WT41u software.

Note:

In order to communic ate with the U ART at its m aximum data r ate using a standar d PC, an accel erated serial

port adapter card is required for the PC.

Parameter Possible values

Data rate Minimum 1200bps (2% error)

9600bps (1% error)

Maximum 3Mbps (1% error)

Flow control RTS/CTS or None

Parity None, Odd or Even

Number of stop bits 1 or 2

Bits per channel 8

Table 12: Possible UART Settings

The UART interf ace is c apabl e of r esetting WT41u upon recept ion of a break s ignal. A br eak is identif ied b y a

continuous logic low (0V) o n the UART_RX terminal, as s hown in Figure 10. If tBRK is longer th an the value,

defined by PSKEY_HOST_IO_UART_RESET_TIMEOUT, (0x1a4), a reset will occur. This feature allows a

host to initialise the system to a known state. Also, WT41u can emit a break character that may be used to

wake the host.

Figure 10: Break Signal

Table 17 shows a list of commonly used data rates and their associated values for

PSKEY_UART_BAUD_RATE (0x204). There is no requirement to use these standard values. Any data rate

within the supported range can be set in the PS Key according to the formula in Equation 1.

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Equation 1: Data Rate

Data rate [bits/s] Persistent store value

(Hex) Error [bits/s] Error [%]

1200 0x0005 5 1.73

2400 0x000A 10 1.73

4800 0x0014 20 1.73

9600 0x0027 39 -0.82

19200 0x004F 79 0.45

38400 0x009D 157 -0.18

57600 0x00EC 236 0.03

76800 0x013B 315 0.14

115200 0x01D8 472 0.03

230400 0x03B0 944 0.03

460800 0x075F 1887 -0.02

921600 0x0EBF 3775 0

1382400 0x161E 5662 -0.01

1843200 0x1D7E 7550 0

2764800 0x2C3D 11325 0

Table 13: Standard Data Rates

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6.1 UART Bypass

Figure 11: UART Bypass Architecture

6.2 UART Configuration While Reset is Active

The UART interfac e for WT41u while the c hip is being held in reset is tris tate. T his will allow the user to daisy

chain devices onto the physical UART bus. The constraint on this method is that any devices connected to

this bus must tristate when WT41u reset is de-asserted and the firmware begins to run.

6.3 UART Bypass Mo de

Alternatively, for devices that do not tristate the UART bus, the UART bypass mode on the chipset can be

used. T he default state of the chips et af ter reset is de-asser ted; this is f or the hos t UART bus to be connec ted

to the chipset UART, thereby allowing communication to the chipset via the UART. All UART bypass mode

connections are implemented using CMOS technology and have signalling levels of 0V and VDD.

In order to apply the UART bypass mode, a BCCMD command will be issued to the chipset. Upon this issue, it

will switch the bypass to PIO[7:4] as Figure 11 indicates. Once the bypass mode has been invoked, WT41u

will enter the Deep Sleep state indefinitely.

In order to re-establish communication with WT41u, the chip must be reset so that the default configuration

takes effect.

It is important for the host to ensure a clean Bluetooth disconnection of any active links before the bypass

mode is invoked. Therefore, it is not possible to have active Bluetooth links while operating the bypass mode.

The current consumption for a device in UART bypass mode is equal to the values quoted for a device in

standby mode.

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7 USB Interface

This is a full speed ( 12Mbits /s) USB interf ace f or comm unicating w ith other c om patible dig ital devices . WT41u

acts as a USB peripheral, responding to requests from a master host controller such as a PC.

The USB interface is capable of driving a USB cable directly. No external USB transceiver is required. The

device operates as a USB peripheral, responding to requests from a master host controller such as a PC.

Both the OHCI and the UHCI standards are supported. The set of USB end poi nts implem ented can beh a ve a s

specif ied in th e USB sectio n of the Bluetoot h v2.1 + EDR s pecification or a lternativel y can a ppear as a set of

endpoints appropriate to U SB aud io de vices suc h as speak er s.

As USB is a master/slave oriented system (in common with other USB peripherals), WT41u only supports

USB Slave operation.

7.1 USB Data Connections

The USB data lines emerge as pins USB_DP and USB_DN. These terminals are connected to the internal

USB I/O buffers of the the chipset, therefore, have a low output impedance. To match the connection to the

character istic impedance of the USB cab le, r es istor s m ust be p laced i n s eries w ith U S B_D P/U SB _DN an d the

cable.

7.2 USB Pull-Up resistor

WT41u features an internal USB pull-up resistor. This pulls the USB_DP pin weakly high when WT41u is

ready to enumerate. It signals to the PC that it is a full speed (12Mbits/s) USB device.

The USB internal pull-up is implemented as a current source, and is com pliant with section 7.1.5 of the U SB

specif ication v1.2. T he internal pull-up pulls USB_DP high to at least 2.8V when loaded with a 15kΩ 5% pull-

down resistor (in the hub/host) when VDD_PADS = 3.1V. This presents a Thevenin resistance to the host of

at least 900Ω. Alternatively, an external 1.5kΩ pull-up resistor can be placed between a PIO line and D+ on

the USB cable. The firm ware must be alerted to which mode is used by setting PSKEY_USB_PIO_PULLUP

appropriately. The default setting uses the internal pull-up resistor.

7.3 USB Power Supply

The USB specification dictates that the minimum output high voltage for USB data lines is 2.8V. To safely

meet the USB specification, the voltage on the VDD supply terminal must be an absolute minimum of 3.1V.

Silicon Labs recommends 3.3V for optimal USB signal quality.

7.4 Self-Powered Mode

In self-powered mode, the circuit is powered from its own power supply and not from the VBUS (5V) line of the

USB cable. It draws only a small leakage current (below 0.5mA) from VBUS on the USB cable. This is the

easier mode for which to design, as the design is not limited by the power that can be drawn from the USB

hub or root port. However, it requires that VBUS be connected to WT41u via a resistor network (Rvb1 and

Rvb2), so WT41u can detect when V BUS is po wered u p. T he chipset w ill not pull USB_DP high when VBUS is

off.

Self-po wered USB designs (powered f rom a batter y or PSU) mus t ensure that a PIO line is allocated f or USB

pullup purp oses. A 1.5k Ω 5% pull-up resistor between USB_DP and the selected PIO line should be fitted to

the design. Failure to fit this resistor may result in the design failing to be USB compliant in self-powered

mode. The internal pull-up in the chipset is only suitable for bus-powered USB devices, e.g., dongles.

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Figure 12: USB Connections for Self-Powered Mode

The terminal marked USB_ON can be any free PIO pin. The PIO pin selected must be registered by setting

PSKEY_USB_PIO_VBUS to the corresponding pin number.

Identifier Value Function

Rs 27Ω nominal Impedance matching to USB cable

Rvb1 22kΩ 5% VBUS ON sense divider

Rvb2 47kΩ 5% VBUS ON sense divider

Figure 13: USB Interface Component Values

7.5 Bus-Powered Mode

In bus-powered mode, the application circuit draws its current from the 5V VBUS supply on the USB cable.

WT41u negotiates with the PC during the USB enumeration stage about how much current it is allowed to

consume. On power-up th e dev ice m ust not dra w more than 1 00 m A but after being c onfigure d it can dra w up

to 500 mA.

For WT41u, the USB power descriptor should be altered to reflect the amount of power required. This is

accomplished by setting PSKEY_USB_MAX_POWER (0x2c6). This is higher than for a Class 2 application

due to the extra current drawn by the Transmit RF PA. By defaul t for WT41u the setting is 300 mA.

When selecting a regulator , be aware that VBUS may go as low as 4.4V. The inrush current (when charging

reservoir and supply decoupling capacitors) is limited by the USB specification. See the USB Specification.

Some app lications m ay require sof t start circ uitry to lim it inrush curr ent if m ore than 10uF is present bet ween

VBUS and GND. T he 5 V VBU S l in e emerging f r om a PC is of ten e lec tric al l y noisy. As w ell as regulat ion d o wn

to 3.3V and 1.8V, applications should include careful filtering of the 5V line to attenuate noise that is above the

voltage regu lator bandwidth. Excessive noise on WT41u supply pins will result in reduced receiver sensitivity

and a distorted RF transmit signal.

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Figure 14: USB Connections for Bus-Po wered Mode

7.6 USB Suspend Current

All USB devices must permit the USB controller to place them in a USB suspend mode. While in USB

Suspend, bus -powered devic es mus t not draw m ore than 2. 5m A from USB VBUS (self -powered de vices m ay

draw m ore than 2.5m A from their own supp ly). T his current dr aw requirem ent prevents operation of the radio

by bus-powered devices during USB Suspend.

When computing suspend current, the current from VBUS through the bus pull-up and pull-down resistors

must be included. The pull-up resistor at the device is 1.5 kΩ. (nominal). T he pull-down resistor at the hub is

14.25kΩ. to 24.80kΩ. T he pull-up voltage is nominall y 3.3V, which means that holding one of the signal lines

high takes approximately 200uA, leaving only 2.3mA available from a 2.5mA budget. Ensure that external

LEDs and/or amplifiers can be turned off by the chipset. The entire circuit must be able to enter the suspend

mode.

7.7 USB Detach and Wake-Up Signaling

WT41u can provide out-of-band signaling to a host controller by using the control lines called USB_DETACH

and USB_WAKE_UP. These are o ut sid e th e USB spec if icatio n ( no wir es ex ist f or them inside t he USB cabl e) ,

but can be useful when embedding WT41u into a circuit where no external USB is visible to the user. Both

control lines are shared with PIO pins and can be assigned to any PIO pin by setting

PSKEY_USB_PIO_DETACH and PSKEY_USB_PIO_WAKEUP to the selected PIO number.

USB_DETACH is an input which, when asserted high, causes WT41u to put USB_DN and USB_DP in high

impedance state and turns off the pull-up resistor on DP. This detaches the device from the bus and is

logically equivalent t o unplugging the device. W hen USB_DETACH is taken low, WT41u will connect back to

USB and await enumeration by the USB host.

USB_WAKE_UP is an active high output (used only when USB_DETACH is active) to wake up the host and

allow USB comm unication to recomm ence. It replac es the function of the soft war e USB WAKE_U P message

(which runs over the USB cable) and cannot be sent while the chipset is effectively disconnected from the

bus.

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Figure 15: USB_Detach and USB_Wake_Up Signals

7.8 USB Driver

A USB Bluetooth device driver is required to provide a software interface between the chipset and Bluetooth

software running on the host computer. Please, contact Silicon Labs support at http://www.silabs.com for

suitable dri vers .

7.9 USB v2.0 Compliance and Compatibility

Although WT41u meets the USB specification, Silicon Labs cannot guarantee that an application circuit

designed around the m odule is USB c ompliant. T he choice of app lication circ uit, component choice and PCB

layout al l aff ect USB signal qual ity and electric al character istics. The inf ormation in this doc ument is intend ed

as a guide and shou ld be read in association with the USB specification, with particular attention being given

to Chapter 7. Independent USB qualification m ust be sought before an application is deemed USB compliant

and can bear the USB logo. Such qualification can be obtained from a USB plugfest or from an independe nt

USB test house.

Terminals USB_DP and USB_DN adhere to the USB Specification v2.0 (Chapter 7) electrical requirements.

The chipset is com patible with USB v2.0 host controllers; under these circum stances the t wo ends agr ee the

mut ually acceptable rate of 12Mbits/s according to the USB v2.0 specification.

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8 Serial Peripheral Interface (SPI)

The SPI por t can be used f or system debugging . It can also be used for program ming the Fl ash mem ory and

setting the PSKEY configurations. WT41u uses 16-bit d ata a nd 1 6-bit ad dr ess s erial p er ipher a l in terface, wher e

transactio ns ma y occur when the interna l process or is running or is stopped. SPI interfac e is connected us ing

the MOSI, MISO, CSB and CLK pins. Please, contact the Silicon Labs support at http://www.silabs.com for

detailed inf ormation about the instruction cycle.

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9 PCM Codec Interface

PCM is a standard method used to digitize audio (particularly voice) for transmission over digital

comm unication ch annels . Thr ough its PC M inter fac e, WT41u has hard ware sup port for c ontinual trans m ission

and reception of PCM data, thus reducing processor overhead for wireless headset applications. WT41u

off ers a bi direc t ion al di gi tal aud io int er f ace t hat routes direc tly into t he baseb and la yer of the on-c h ip f irmware.

It does not pass through the HCI protocol layer.

Hardware on WT41u allows the data to be sent to and received from a SCO connection. Up to three SCO

connections can be supported by the PCM interface at any one time.

WT41u can operate as the PCM interface master generating an output clock of 128, 256 or 512kHz. When

configured as PCM interface slave, it can operate with an input clock up to 2048kHz. WT41u is compatible

with a variety of clock formats, including Long Frame Sync, Short Frame Sync and GCI timing environments.

It supports 13-bit or 16-bit linear, 8-bit µ-law or A-law companded sample formats at 8ksamples/s and can

receive and transmit on any selection of three of the first four slots following PCM_SYNC. The PCM

configuration options ar e enab led b y setting PS K EY_ PCM_CONFI G32.

WT41u interfaces directly to PCM audio devices.

NOTE: Analog audio lines are very sensitive to RF disturbance. Use good layout practices to ensure noise

less audio. Make s ure t h at t he r eturn pa th f or the a ud io s ignals fo ll ows the for ward c urr ent all th e way as c lose

as possible and use fully differential signals when possible. Do not compromise audio routing.

9.1 PCM Inter fa ce Master/S l a ve

When configured as the master of the PCM interface, WT41u generates PCM_CLK and PCM_SYNC.

Figure 16: PCM Interface Master

When configured as the Slave of the PCM interface, WT41u accepts PCM_CLK rates up to 2048kHz.

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Figure 17: PCM Interface Slave

9.2 Long Frame Sync

Long Frame Sync is the name given to a clocking format that controls the transfer of PCM data words or

samples. In Long Frame Sync, the rising edge of PCM_SYNC indicates the start of the PCM word. When

WT41u is configured as PCM master, generating PCM_SYNC and PCM_CLK, then PCM_SYNC is 8-bits

long. W hen WT41u is configured as PCM Slave, PCM_SYNC may be from two consecutive falling edges of

PCM_CLK to half the PCM_SYNC rate, i.e., 62.5s long.

Figure 18: Long Frame Sync (Shown with 8-bit Companded Sample)

WT41u samples PCM_IN on the falling edge of PCM_CLK and transmits PCM_OUT on the rising edge.

PCM_OUT may be configured to be high impedance on the falling edge of PCM_CLK in the LSB position or

on the rising edge.

9.3 Short Frame S ync

In Short Frame Sync, the falling edge of PCM_SYNC indicates the start of the PCM word. PCM_SYNC is

always one clock cycle long.

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Figure 19: Short Frame Sync (Shown with 16-bit Sample)

As with Long Frame Sync, WT41u samples PCM_IN on the falling edge of PCM_CLK and transmits

PCM_OUT on the rising edge. PCM_OUT may be configured to be high impedance on the falling edge of

PCM_CLK in the LSB position or on the rising edge.

9.4 Multi-slot Operation

More than one SCO connection over the PCM interface is supported using multiple slots. Up to three SCO

connections can be carried over any of the first four slots.

Figure 20: M ulti-slot Operation with Two Slots and 8-bit Companded Sam ples

9.5 GCI In terfa ce

WT41u is com patible with t he GCI, a s tandar d synchronous 2B+D ISDN tim ing interf ace. T he two 64k bits/s B

channels can be accessed when this mode is configured.

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Figure 21: GCI Interface

The start of frame is indicated by the rising edge of PCM_SYNC and runs at 8kHz. With WT41u in Slave

mode, the frequency of PCM_CLK can be up to 4.096MHz.

9.6 Slots and Sample Formats

WT41u can receive and transmit on any selection of the first four slots following each sync pulse. Slot

durations can be either 8 or 16 clock cycles. Durations of 8 clock cycles may only be used with 8-bit sample

formats. Durations of 16 clocks may be used with 8-bit, 13-bit or 16-bit sample formats.

WT41u supports 13-bit linear, 16-bit linear and 8-bit -law or A-law sample formats. The sample rate is

8ksamples/s. The bit order may be little or big endian. When 16-bit slots are used, the 3 or 8 unused bits in

each slot may be filled with sign extension, padded with zeros or a programmable 3-bit audio attenuation

compatible with some Motorola codecs.

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Figure 22: 16-bit Slot Length and Sample Formats

9.7 Additional Features

WT41u has a mute f acility that f orces PCM_OUT to be 0. In m ast er mode, PCM_S YNC m a y also b e for ced to

0 while keeping PCM_CLK running which some codecs use to control power down.

9.8 PCM_CLK and PCM_SYNC Generation

WT41u has two methods of generating PCM_CLK and PCM_SYNC in master mode. The first is generating

these signals b y DDS from the chipset internal 4MHz clock. Using this mode limits PCM_CLK to 128, 256 or

512kHz and PCM_SYNC to 8kHz. The second is generating PCM_CLK and PCM_SYNC by DDS from an

internal 48MHz clock (which allows a greater range of frequencies to be generated with low jitter but

consumes more power). This second method is selected by setting bit 48M_PCM_CLK_GEN_EN in

PSKEY_PCM_CONFIG32. When in this mode and with long frame sync, the length of PCM_SYNC can be

either 8 or 16 cycles of PCM_CLK, determined by LONG_LENGTH_SYNC_EN in PSKEY_PCM_CONFIG32.

The Equation 2 describes PCM_CLK frequency when being generated using the internal 48MHz clock:

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Equation 2: PCM_CLK Frequency When Being Generated Using the Internal 48MHz Clock

The frequency of PCM_SYNC relative to PCM_CLK can be set using Equation 3:

Equation 3: PCM_SY NC Frequency Relative to PCM_CLK

CNT_RATE, CNT_LIMIT and SYNC_LIMIT are set using PSKEY_PCM_LOW_JITTER_CONFIG. As an

example, to generate PCM_CLK at 512kHz with PCM_SYNC at 8kHz, set

PSKEY_PCM_LOW_JITTER_CONFIG to 0x08080177.

9.9 PCM Configuration

The PCM configuration is set using two PS Keys, PSKEY_PCM_CONFIG32 detailed in Table 18 and

PSKEY_PCM _LOW_J ITTER_CONF IG in T able 19. T he def ault for PSKE Y_PCM _CONF IG32 is 0x0080 000 0,

i.e., first slot following sync is active, 13-bit linear voice format, long frame sync and interface master

generating 256kHz PCM_CLK from 4MHz internal clock with no tri-state of PCM_OUT.

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Name Bit

position Description

- 0 Set to 0

SLAVE MODE EN 1 0 selects Master mode with internal generation of PCM_CLK and

PCM_SYNC. 1 selects Slave mode requiring externally generated

PCM_CLK and PCM_SYNC. This should be set to 1 if

48M_PCM_CLK_GEN_EN (bit 11) is set.

SHORT SYNC EN 2 0 selects long frame sync (rising edge indicates start of frame),

- 3 Set to 0

SIGN EXTENDED

EN 4 0 selects long frame sync (rising edge indicates start of frame), 1 selects

short frame sync (falling edge indicates start of frame).

LSB FIRST EN 5 0 transmits and receives voice samples MSB first, 1 uses LSB

TX TRISTATE EN 6 0 transmits and receives voice samples MSB first, 1 uses LSB

TX TRISTATE

RISING EDGE EN 7 0 tristates PCM_OUT immediately after the falling edge of PCM_CLK in the

last bit of an active slot, assuming the next slot is also not active. 1 tristates

PCM_OUT after the rising edge of PCM_CLK.

SYNC SUPPRESS

EN 8 0 enables PCM_SYNC output when master, 1 suppresses PCM_SYNC

whilst keeping PCM_CLK running. Some CODECS utilize this to enter a

low power state

GCI MODE EN 9 1 enables GCI mode.

MUTE EN 10 1 forces PCM_OUT to 0.

48M PCM CLK GEN

EN 11 0 sets PCM_CLK and PCM_SYNC generation via DDS from internal 4

MHz clock. 1 sets PCM_CLK and PCM_SYNC generation via DDS from

internal 48 MH z clock .

LONG LENGTH

SYNC EN 12 0 sets PCM_SYNC length to 8 PCM_CLK cycles and 1 sets length to 16

PCM_CLK cycles. Only applies for long frame sync and with

48M_PCM_CLK_GEN_EN set to 1.

- [20:16] Set to 0b00000.

MASTER CLK RATE [22:21] Selects 128 (0b01), 256 (0b00), 512 (0b10) kHz PCM_CLK frequency

when master and 48M_PCM_CLK _GEN_EN (bi t 11) is low.

ACTI VE SLO T [26:23] Default is 0001. Ignored by firmaware

SAMPLE FORMAT [28:27] Selects between 13 (0b00), 16 (0b01), 8 (0b10) bit sample with 16 cycle

slot duration 8 (0b11) bit sample 8 cycle slot duration.

Table 14: PSKEY_PCM_CONFIG32 description

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Name Bit position Description

CNT LIMIT [12:0] Sets PCM_CLK counter limit

CNT RATE [23:16] Sets PCM_CLK count rate

SYNC LIMIT [31:24] Sets PCM_SYNC division relative to PCM_CLK

Table 15: PSKEY_PCM_LOW_JI TTER_CONFIG Description

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10 I/O Parallel Ports

Six lines of programmable bidirectional input/outputs (I/O) are provided. All the PIO lines are power from VDD.

PIO lines can be configured through software to have either weak or strong pull-ups or pull-downs. All PIO

lines are configured as inputs with weak pull-downs at reset. Any of the PIO lines can be configured as

interrupt request lines or as wake-up lines from sleep modes.

WT41u has a general purpose analogue interface pin AIO[1]. This is used to access internal circuitry and

control signals. It may be configured to provide additional functionality.

Auxiliary functions available via AIO[1] include an 8-bit ADC and an 8-bit DAC. T ypica lly the ADC is used for

battery voltage measurement. Signals selectable at this pin include the band gap reference voltage and a

variety of clock signals: 48, 24, 16, 8MHz and the XTAL clock frequency. When used with analogue signals,

the voltage range is constrained by the analogue supply voltage internally to the module (1.8V). When

configured to drive out digital level signals (e.g., clocks), the output vol tag e level is determined by VDD.

10.1 PIO Defaults

Silicon Labs cannot guarantee that these terminal functions remain the same. Refer to the software release

note for the implementation of these PIO lines, as they are firmware build-specific.

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11 Reset

WT41u may be reset from several sources: RESET pin, power on reset, a UART break character or via

software configured watchdog timer. T he RESET pin is an active low reset and is internally filtered using the

internal low frequency clock oscillator. A reset will be performed between 1.5 and 4.0ms following RESETB

being active. It is recommended that RESET be applied for a period greater than 5ms.

The power on reset occurs when the VDD_CORE supply internally to the module falls below typically 1.5V

and is releas ed when VDD_CO RE rises above t ypical ly 1.6V. At reset the dig ital I/O pins are set to in puts for

bidirectional pins and outputs are tri-state.

The reset should be held active at power up until all the supply voltages have stabilized to ensure correct

operatio n of the interna l flash m emor y. Following f igure s hows an exam ple of a s imple po wer up reset circuit.

Time constant of the RC circuitry is set so that the supply voltage is safely stabilized before the reset

deactivates.

Figure 23: Example of a simple power o n reset circuit.

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11.1 Pin States on Reset

Pad name State

PIO[7:2] Input, weak pull-down

PCM_OUT 3-state, weak pull-down

PCM_IN Input, weak pull-down

PCM_SYNC Input, weak pull-down

PCM_CLK Input, weak pull-down

UART_TX 3-state, weak pull-up

UART_RX Input, weak pull-down

UART_RTS 3-state, weak pull-up

UART_CTS Input, weak pull-down

USB+ Input, weak pull-down

USB- Input, weak pull-down

SPI_CSB Input, weak pull-down

SPI_CLK Input, weak pull-down

SPI_MOSI Input, weak pull-down

SPI_MISO 3-state, weak pull-down

AIO[1] Output, dr i ving lo w

Table 16: Pin States on Reset

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12 Certifications

12.1 Bluetooth

The WT41u is Bluetooth qualified and the declaration ID is D032265 (QDID 88818)

12.2 FCC

This device complies with Part 15 of the 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

undesirable operation.

Any changes or modifications not expressly approved by Silicon Labs could void the user’s authority to

operate the equipment.

FCC RF Radiation Exposure Stateme n t:

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 compliance. This transmitter

meet s both porta ble a nd m obi le limits as demonstr ated in the RF Ex posur e A na l ysis . This transmitter m us t not

be co-locate d or oper at ing in c onj unc tion with any other antenn a or t ransmitter except in ac cor da nc e with FCC

multi-transm itter produc t procedur es. As l ong as t he conditi on above is met, further tr ansmitter testing w ill not

be required. However, the OEM integrator is still responsible for testing their end-product for any additional

compliance requirements required with this module installed (for example, digital device emissions, PC

peripheral requirements, etc.).

OEM Responsibil ities to comply with FCC Regulations

The WT41u Module has been certified for integration into products only by OEM integrators under the

following condition:

• The antenna(s) must be installed such that a minimum separation distance of 42 mm is

maintained between the radiator (antenna) and all persons at all times.

• The transmitter module must not be co-located or operating in conjunction with any other

antenna or transmitter except in accordance with FCC multi-transmitter product procedures.

As long as the conditions above are met, further transmitter testing will not be required. However, the OEM

integrator is still resp onsible for testing their end-pr oduct for an y add itional com pliance requirem ents requir ed

with this module installed (for example, digital device emissions, PC peripheral requirements, etc.).

Note: In the event that this condition cannot be met (for certain configurations or co-location with another

transm itter), then the FCC authorization is no longer c onsidered vali d and the FCC ID cannot be used on the

final pro duct. I n these c ircu ms tances, the OEM i ntegr ator will be res pons ible f or re-evalu ating t he end produ ct

(including the transmitter) and obtaining a separate FCC authorization.

End Product Labeling

The W T41u Module is labeled with its own FCC ID. If the FCC ID is not visible when the module is installed

inside another device, then the outside of the device into which the module is installed must also display a

label referring to the enclosed module. In that case, the final end product must be labeled in a visible area with

the following:

"Contains Transmitter Module FCC ID: QOQWT41u"

"Contains FCC ID: QOQWT41u"

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The OEM integrator must not provide information to the end user regarding how to install or rem ove this RF

module or change RF related parameters in the user manual of the end product.

12.3 ISEDC

This radio transmitter (IC: 5123A-WT41U) has been approved by Industry Canada to operate with the

embedded chip antenna. Other antenna types are strictly prohibited for use with this device.

This device complies with Industry Canada’s license-exempt RSS standards. Operation is subject to the

following two conditions:

1. This device may not cause interference; and

2. This de vic e m ust acc ept an y interf erenc e, incl uding interf erenc e that m a y cause undes ired op erat ion

of the device.

RF Exposure Statement

Exception from routine SAR evaluation limits are given in RSS-102 Issue 5. WT41u meets the given

requirements when t he minim um separatio n distance t o human bod y 40 mm. RF exposure or SAR evaluat ion

is not requ ired whe n the se paration dis tance is 40 mm or m ore. If the separ ation distance is less tha n 40 mm

the OEM integrator is responsible for evaluating the SAR.

OEM Resp onsibil ities to c om pl y with IC Regulat ions T he WT41u Module h as bee n certif ied for integr ati on int o

products only by OEM integrators under the following conditions:

• The antenna(s) must be installed such that a minimum separation distance of 40 mm is maintained

between the radiator (antenna) and all persons at all times.

• The transmitter module must not be co-located or operating in conjunction with any other antenna or

transmitter.

As long as the two conditions above are met, further transmitter testing will not be required. However, the

OEM integrator is still responsible for testing their end-product for any additional compliance requirements

required with this module installed (for example, digital device emissions, PC peripheral requirements, etc.).

Note: In the event that these conditions cannot be m et (for certain configurations or co-location with another

transm itter), then the IC au thorization is no l onger cons idered valid and the IC I D cannot be us ed on the final

product. In these circumstances, the OEM integrator will be responsible for re-evaluating the end product

(including the transmitter) and obtaining a separate IC authorization.

End Product Labeling

The WT 41u m odule is labe led with its o wn IC ID. If the IC ID is not visible when the m odule is instal led inside

another device, then the outside of the device into which the module is installed must also display a label

refer ring to the e nclosed m odule. In that cas e, the f inal end product m ust be labeled in a vis ible area with th e

following:

"Contains Transmitter Module IC: 5123A-WT41u"

"Contains IC: 5123A-WT41u"

The OEM integrator has to be aware not to provide information to the end user regarding how to install or

remove this RF module or change RF related parameters in the user manual of the end product.

12.3.1 ISEDC (Français)

Cet émetteur radio (IC : 5123A-WT41u) a reçu l'approbation d'Industrie Canada pour une exploitation avec

l'antenne puce incorporée. Il est strictement interdit d'utiliser d'autres types d'antenne avec cet appareil.

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Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio exempts de

licence. L’exploitation est autorisée aux deux conditions suivantes:

1. L’appareil ne doit pas produire de brouillage; et

2. L’appar eil doit accept er tout brouillage rad ioélectriq ue subi, mêm e si le brouillage est sus ceptible de

provoquer un fonctionnement non désiré de l’appareil.

Déclaration relative à l'exposition aux radiofréquences (RF)

Les limites applicables à l’exemption de l’évaluation courante du DAS sont énoncées dans le CNR 102, 5e

édition. Le module Bluetooth WT41u répond aux exigences données quand la distance de séparation

minim um par rappor t a u c o r ps humain est de 40 mm. L'évaluat ion de l'exposi tion aux RF ou du DAS n'est pas

requise quand la distance de séparation est de 40 mm ou plus. Si la distance de séparation est inférieure à 40

mm, il incombe à l'intégrateur FEO d'évaluer le DAS.

Responsabilités du FEO ayant trait à la conformité avec les règlements IC

Le Module Bluetooth WT41u a été certifié pour une intégration dans des produits uniquement par les

intégrateurs FEO dans les conditions suivantes:

• La ou les antennes doi vent être insta llées de tell e façon qu'une distance de s éparation m inimum de 40 mm

soit maintenue entre le radiateur (antenne) et toute personne à tout moment.

• Le m odule émet teur ne doit pas être ins tall é au m êm e endroit ou fonc tionner c onjoin tem ent avec to ute au tre

antenne ou émetteur.

Dès lors que les deux conditions ci-dessus sont respectées, aucun test supplémentaire de l’émetteur n’est

obligatoir e. C ependa nt, il inc ombe touj our s à l' intégra teur FEO de tes ter la conf orm ité de son pro duit f inal vis -

à-vis de toute exigence supplémentaire requise avec ce module installé (par exemple, émissions de

dispositifs numériques, exigences relatives aux matériels périphériques PC, etc).

Note: S'il s'avère que ces conditions ne peuvent être respectées (pour certaines configurations ou la

colocation avec un autre émetteur), alors l'autorisation IC n'est plus consi dérée c om me valide et l'ident if iant IC

ne peut plus êtr e emplo yé sur le produ it f inal . Dans c es c irc ons tanc es, l'intégr ate ur FEO aura la r esponsabil i té

de réévaluer le produit final (y compris l'émetteur) et d'obtenir une autorisation IC distincte.

Étiquetage du produit final

L'étiquette du Module WT41u porte son propre identifiant IC. Si l'identifiant IC n'est pas visible quand le

module est installé à l'intérieur d'un autre appareil, alors l'extérieur de l'appareil dans lequel le module est

installé doit aussi porter une étiquette faisant référence au module qu'il contient. Dans ce cas, une étiquette

comportant les informations suivantes doit être apposée sur une partie visible du produit final.

"Contient le module émetteur IC: 5123A-WT41U"

"Contient IC : 5123A-WT41U"

L'intégrateur FEO doit être conscient de ne pas fournir d'inf ormations à l'utilisateur final perm ettant d'installer

ou de retirer ce module RF ou de changer les paramètres liés aux RF dans le mode d'emploi du produit final.

12.4 CE

The Declaration of Compliance and the test documentation can be consulted in www.silabs.com.

Please n ote that ever y app licat ion using the W T41-A or WT41-N will nee d to perform the radio EMC tes ts on

the end product acc or ding to EN 301 489-17.

RF exposure requirements must be verified in an end produc t ass embly.

Test documentation and software for the EN 300 328 radiated spurious emissions testing can be requested

from the Silicon Labs support.

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12.5 MIC Japan

The WT41u module in certified for Japan. Certification number: 209-J00231 Since September 1, 2014 it is

allowed ( an d h igh l y rec om mended) that a manuf actur er who int egrates a rad io modu le in t heir host e qu ipment

can place the certification m ark and certification number (the same mark ing/num ber as depicted on the label

of the radio module) on the outside of the host equipment. The certification mark and certification number

must be p lace d clos e to th e text in th e Jap anese lang uage which is provi ded b elo w. This c hange in th e R adio

Law has b een m ade in ord er to ena ble users of the com bination of host an d radio m odule to verif y if they are

actually using a radio device which is approved for use in Japan.

当該機器には電波法に基づく、技術基準適合証明等を受けた特定無線設備を装着している。

Translation: “This equipment contains specified radio equipment that has been certified to the Technical

Regulation Conformity Certification under the Radio Law.”

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12.6 Qualified Antenna Types for WT41u-E and WT41u-N

This device has been d esig ned to operat e with a stand ard 2.14 dBi dipole antenna. An y antenna of a diff erent

type or with a gain higher than 2.14 dBi is strictly prohibited for use with this device. Using an antenna of a

different type or gain more than 2.14 dBi will require additional testing for FCC, CE and IC. The required

antenna im pedanc e is 50 Ω.

Antenna type Maximum gain

Dipole 2.14 dBi

Table 17: Qualified Antenna Types for WT41u-E/N

To reduce potential radio interference to other users, the antenna type and its gain should be so chosen that

the equivalent isotropically radiated power (EIRP) is not more than that permitted for successful

communication.

Any standard 2.14 dBi dipole antenna can be used without an additional application to FCC.

12.7 Moisture Sensitivity Level (MSL)

Moisture sensitivity level (MSL) of this product is 3. For the handling instructions please refer to JEDEC J-

STD-020 and JEDEC J-STD-033.

If baking is required, devices may be baked for 12 hours at 125°C +/-5°C for high temperature device

containers.

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Disclaimer

Silicon Labs intends to provide customers with the latest, accurate, and in-depth documentation of all peripherals and modules available for system and software implementers using or

intending to use the Silicon Labs products. Characterization data, available modules and peripherals, memory sizes and memory addresses refer to each specific device, and "Typical"

parameters provided can and do vary in different applications. Application examples described herein are for illustrative purposes only. Silicon Labs reserves the right to make changes

without further notice and limitation to product information, specifications, and descriptions herein, and does not give warranties as to the accuracy or completeness of the included

information. Silicon Labs shall have no liability for the consequences of use of the information supplied herein. This document does not imply or express copyright licenses granted

hereunder to design or fabricate any integrated circuits. The products are not designed or authorized to be used within any Life Support System without the specific written consent of

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destruction including (but not limited to) nuclear, biological or chemical weapons, or missiles capable of delivering such weapons.

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