SEMTECH XE1203FI063TRLF

XE1203F
XE1203F
433 MHz / 868 MHz / 915 MHz
Low-Power, Integrated UHF Transceiver
GENERAL DESCRIPTION
KEY PRODUCT FEATURES
• RF output power: up to +15 dBm
• High reception sensitivity: down to –114 dBm
(typical)
• Low power consumption:
RX = 14 mA; TX = 62 mA @15 dBm (typical)
• Supply voltage down to 2.4V
• Data rate from 1.2 to 152.3 kbit/s, NRZ coding
• Konnex-compatible operation mode
• 11-bit Barker encoder/decoder
• On-chip frequency synthesizer with minimum
frequency resolution of 500 Hz
Continuous phase 2-level FSK modulation
Received data pattern recognition
• Bit-Synchronizer for incoming data/clock
synchronization and recovery
• RSSI (Received Signal Strength Indicator)
• FEI (Frequency Error Indicator)
• RoHS green package
The XE1203F is a single chip transceiver operating in
the 433, 868 and 915 MHz license-free ISM (Industry
Scientific and Medical) frequency bands. Its highly
integrated architecture allows for minimum external
components while maintaining design flexibility. All
major
RF
communication
parameters
are
programmable and most of them can be dynamically
set. The XE1203F offers the excellent advantage of
high data rate communication at rates of up to 152.3
kbit/s, without the need to modify the number or
parameters of the external components. The
XE1203F is optimized for low power consumption
while offering high RF output power and exceptional
receiver sensitivity. The device is suitable for
applications which have to satisfy either the European
(ETSI-300-220) or the North American (FCC part 15)
regulatory standards. TrueRF™ technology enables a
low –cost external component count (elimination of
the SAW filter) whilst still satisfying ETSI and FCC
regulations.
APPLICATIONS
•
•
•
•
ORDERING INFORMATION
Automated Meter Reading (AMR)
Home Automation and Access Control
High-Quality Speech, Music and Data over RF
Applications requiring Konnex-compatibility
Rev 1 March 2007
Part number
Temperature
range
Package
XE1203FI063TRLF
-40 °C to +85 °C
VQFN48
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1
XE1203F
Table of Contents
1
2
3
3.1
3.2
3.2.1
3.2.2
4
4.1
4.1.1
4.1.2
4.1.3
4.1.4
4.1.5
4.1.6
4.1.7
4.1.8
4.2
4.2.1
4.2.2
4.3
4.3.1
5
5.1
5.2
5.2.1
5.2.2
5.2.3
5.2.4
5.2.5
5.2.6
5.2.7
5.2.8
5.3
5.3.1
5.4
5.5
5.6
6
6.1
6.2
6.3
6.4
6.5
7
Functional Block Diagram...................................................................................................................3
Pin Description.....................................................................................................................................4
Electrical Characteristics ....................................................................................................................5
Absolute Maximum Operating Ranges ..................................................................................................5
Specifications .........................................................................................................................................5
Operating Range....................................................................................................................................5
Electrical Specifications .........................................................................................................................5
General Description .............................................................................................................................7
The Receiver Section.............................................................................................................................7
LNA & Receiver modes..........................................................................................................................8
Demodulation chain ...............................................................................................................................8
Demodulator...........................................................................................................................................8
Bit synchronizer......................................................................................................................................9
The DATA and DATAIN pins .................................................................................................................9
Pattern recognition block......................................................................................................................10
RSSI.....................................................................................................................................................10
Frequency Error Indicator – FEI...........................................................................................................12
The Transmitter Section.......................................................................................................................13
Transmitter ...........................................................................................................................................13
Barker encoder/decoder ......................................................................................................................15
The Frequency Synthesizer .................................................................................................................17
Clock Output for external processor ....................................................................................................17
Serial Interface Definition And Principles Of Operation ................................................................18
Serial Control Interface ........................................................................................................................18
Configuration and Status registers.......................................................................................................20
The ConfigSwitch Register...................................................................................................................20
RTParam Configuration Register.........................................................................................................22
FSParam Configuration Register .........................................................................................................23
SWParam Configuration Register - switching parameters ..................................................................24
DataOut Status Register ......................................................................................................................25
ADParam Configuration Register.........................................................................................................25
Pattern register.....................................................................................................................................27
Test Registers and additional settings .................................................................................................28
Operating Modes..................................................................................................................................28
Standard power up sequence for the receiver and transmitter ............................................................28
Selection of the reference frequency ...................................................................................................29
Clock Output Interface .........................................................................................................................30
Default settings at power-up ................................................................................................................30
Application Information.....................................................................................................................31
Matching network of the receiver .........................................................................................................31
Matching network of the transmitter.....................................................................................................31
VCO tank..............................................................................................................................................34
Loop filter of the frequency synthesizer................................................................................................34
Reference crystal for the frequency synthesizer ..................................................................................35
Packaging information ......................................................................................................................36
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XE1203F
The XE1203F is a single-chip UHF transceiver integrated circuit intended for use as a low cost FSK transceiver to
establish a frequency-agile, half-duplex, bi-directional RF link, with NRZ (non-return to zero) data coding. Barker
encoder/decoder hardware can be activated to modulate/demodulate the transmitted signal to reduce the effects of
fixed-frequency in-band interference. The device is available in a VQFN48 package and is designed to provide a
fully functional multi-channel FSK transceiver. It is intended for applications in the 868 MHz European band and the
North American 902-928 MHz ISM band. The single chip transceiver operates down to 2.4V and provides a low
power solution for battery-operated and power sensitive applications. The XE1203F is capable of operating data
rates up to 152.3 kbit/s, making it ideally suited for applications where high data rates are required.
VSS
VSSA
IAMP
QAMP
VDD
VDDA
VSSP
VSSF
VSSD
FUNCTIONAL BLOCK DIAGRAM
VDDF
VDDD
VDDP
1
IAMP
QAMP
SI
RSSI
FAMP
LPF
BBAMP
SO
LIM
CONTROL
DATA
RFA
MATCHING
NETWORK
EN
LNA
FEI
SWITCH
RFB
FAMP
LPF
BBAMP
LIM
PATTERN
MATCHING
LO_BUF
IREF
DIVCTL
MMOD
DIVIDER
DEMOD
BITSYNC
LOGIC
CONTROL
DATAIN
DATA
11 Bits
BARKER
ENCODER
modulator
/n
Synthesizer
CLKXTAL
XE1203 TrueRF™
XE1203
RFOUT
PA
PATTERN
DCLK
PHASE
SHIFTER
11 Bits
BARKER
DECODER
MATCHING
NETWORK
SCK
CH PUMP
PFD
VCO
OSCILLATOR
/n
CLOCK OUT
IREF
POR
TKA
VCO
TANK
TKB
LFB
LOOP
FILTER
XTA
XTB
CLKOUT
TSUPP TMOD(3:0)
POR
XTAL
Figure 1: XE1203F Block Diagram
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3
XE1203F
2
PIN DESCRIPTION
PIN
NAME
1
2
3
4
5
6
7
N.C.
N.C.
N.C.
VSSF
RFA
RFB
VSSP
8
VSSP
9
10
11
RFOUT
VDDP
Test pin
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
VDDF
VSSF
TKA
TKB
VSSF
LFB
VDDD
VSSD
Test pin
Test pin
N.C.
Test pin
Test pin
VSSA
XTA
VSSA
XTB
VDDA
QAMP
IAMP
Test pin
33
34
I/O
IN
IN
Description
Not connected
Not connected
Not connected
Ground for the RF analog blocks
RF input
RF input
Ground for the RF power amplifier
Ground for the RF power amplifier
OUT
IN
RF output
Power supply for the RF power amplifier
Connected to ground
IN
Power supply for the RF analog blocks
Ground for the RF analog blocks
VCO tank
VCO tank
Ground for the RF analog blocks
Loop filter of the PLL
Power supply for the RF digital blocks
Ground for the RF digital blocks
Connected to ground
Connected to ground
Not connected
Connected to ground
Connected to ground
Ground for the analog blocks
Crystal and input of external clock
Ground for the analog blocks
Crystal
Power supply for the analog blocks
Buffered Q output
Buffered I output
Connected to ground
Test pin
IN
Connected to ground
Test pin
IN
Connected to ground
35
EN
IN
3-wire interface communication enable signal
36
37
VDD
SWITCH
IN/OUT
Power supply for the digital blocks
Receiver or Transmitter mode selection
38
SO
OUT
Data output of the 3-wires interface
39
SI
IN
Data input of the 3-wires interface
40
SCK
IN
Input clock of the 3-wires interface
41
CLKOUT
Out
Output clock at quartz frequency divided by 4, 8, 16 or 32
42
43
VSS
DCLK
OUT
Ground for the digital blocks
Transmitter or Receiver clock
44
DATA
IN/OUT
Transmitter input data or Receiver output data
45
DATAIN
IN
Transmitter input data
46
PATTERN
Out
Output of the pattern recognition block
47
48
N.C.
N.C.
IN/OUT
IN/OUT
IN/OUT
IN
IN
IN
IN
IN/OUT
IN/OUT
Not connected
Not connected
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4
XE1203F
3
ELECTRICAL CHARACTERISTICS
3.1
ABSOLUTE MAXIMUM OPERATING RANGES
Stresses above the values listed below in Table 1 may cause permanent device failure. Exposure to absolute
maximum ratings for extended periods may affect device reliability.
Symbol
Description
Min.
Max.
Unit
VDDmax
Supply voltage
-0.4
3.9
V
ML
Receiver input level
-5
dBm
Tmax
Storage temperature
-55
125
°C
Min.
Max.
Unit
Table 1: Absolute Maximum Ratings
The device is ESD sensitive and should be handled with precaution.
3.2
SPECIFICATIONS
3.2.1
Operating Range
Symbol
Description
VDD
Supply voltage
2.4
3.6
V
T
Temperature
-40
85
°C
CLop
Load capacitance on digital ports
-
25
pF
Table 2: Operating Range
3.2.2 Electrical Specifications
Table 3 below gives the electrical specifications of the transceiver under the following conditions:
Supply Voltage VDD = 3.3V, temperature = 25 °C, 2-l evel FSK without pre-filtering, carrier frequency fc = 915 MHz,
frequency deviation ∆f = 55 kHz, bit rate BR = 4.8 kbit/s, Base band filter bandwidth BBW = 200 kHz, bit error rate
BER = 0.1% (measured at the output of the bit synchronizer), LNA input and RF PA output matched to 50Ω,
environment as defined in Section 6, unless otherwise specified.
Symbol
Description
IDDSL
Supply current in sleep mode
IDDST
Supply current in standby mode
IDDR
IDDT
Supply current in receiver mode
Supply current in transmitter mode
(with optimum load-matching)
RFS
RF sensitivity
RFSB
RF sensitivity with Barker
Coding/decoding enabled
FDA
Frequency deviation
CCR
Co-channel rejection
Conditions
Min
Typ
Max
Unit
-
0.2
1
uA
-
0.85
1.10
mA
RFOP = 5 dBm
RFOP = 15 dBm
-
14
33
62
17
40
75
mA
mA
mA
BR = 4.8 kbit/s Mode A (*1)
BR = 4.8 kbit/s Mode B (*1)
BR = 32.7 kbit/s Mode A (*1)
BR = 32.7 kbit/s Mode B (*1)
-
-114
-101
-109
-96
-111
-98
-106
-93
dBm
dBm
dBm
dBm
Quartz oscillator (39 MHz)
enabled
∆f = 200 kHz,
BBW = 600 kHz
BR = 152.3 kbit/s Mode A (*1)
BR = 152.3 kbit/s Mode B (*1)
BR = 1154 bit/s Mode A (*1)
-
-101
-89
-98
-86
dBm
dBm
-
-113
-110
dBm
BR = 1154 bit/s Mode B(*1)
-
-100
-97
dBm
Programmable
1
-
255
kHz
-13
-10
-
dBc
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5
XE1203F
Symbol
Description
Conditions
Min
Typ
Max
Unit
IIP3
Input intercept point
f1 = fLO + 1 MHz
f2 = fLO + 1.945 MHz
Mode A (*1)
Mode B (*1)
-36
-21
-33
-18
-
dBm
dBm
-
200
600
-
kHz
kHz
48
-
dBc
152.3
kbit/s
dBm
dBm
dBm
dBm
BBW
Base band filter bandwidth DSB
Programmable (*2)
ACR
Adjacent channel rejection
funw = fLO + 650 kHz
Pw= - 108dBm, mode A (*1)
45
BR
Bit rate
Programmable
1.2
RFOP
RF output power
Programmable
FR
Synthesizer frequency range
TS_TR
TS_RE
RFOP1
RFOP2
RFOP3
RFOP4
-3
+2
+7
+12
0
+5
+10
+15
-
Transmitter wake-up time
Receiver Baseband wake-up time
Programmable
Each range with its own
external components
From oscillator enabled
From oscillator enabled
433
868
902
-
150
0.5
435
870
928
250
0.8
MHz
MHz
MHz
us
ms
TS_RSSI
RSSI wake-up time
From receiver enabled
-
-
1
ms
TS_RSSIM
RSSI measurement time
TS_OS
Crystal oscillator wake-up time
0.5
Fundamental
rd
3 overtone
TS_FEI
FEI wake-up time
TS_SYNC_AQ
Time for synchronization of the
Barker decoder
Input power of –106 dBm
-
0.3
-
2.5
ms
0.5
ms
ms
-
-
2/BR
ms
-
5
-
ms
Data rate = 1154 bits/s
Chip rate = 12.7 kcps
From Rx enabled
XTAL
Crystal oscillator frequency
FSTEP
VTHR
rd
Fundamental or 3 overtone
-
39
-
MHz
Frequency synthesizer step
Exact step is XTAL / 77 824
-
500
-
Hz
RSSI equivalent input thresholds
Mode A (*1)
Low range:VTHR1
-
-100
-
dBm
VTHR2
-
-95
-
dBm
VTHR3
-
-90
-
dBm
High range:VTHR1
-
-85
-
dBm
VTHR2
-
-80
-
dBm
VTHR3
-
-75
-
dBm
-
-65
-
dBm
SPR
Spurious emissions in Rx mode
(*4)
SCK
Serial Clock frequency
VIH
Digital input level high (*3)
% VDD
75
VIL
Digital input level low (*3)
% VDD
VOH
Digital output level high
VOL
Digital output level low
1
MHz
-
-
%
-
-
25
%
% VDD
75
-
-
%
% VDD
-
-
25
%
Table 3: Electrical Specifications
Notes:
(*1)
Mode A: High sensitivity mode; Mode B: High Linearity mode. As defined in Paragraph 4.1.1.
(*2)
An intermediate bandwidth of 300 kHz can also be selected by using additional settings described in section 5.2.8.
(*3)
Throughout this document, digital signal levels are named “high” or “1”, and “low” or “0”.
(*4)
SPR strongly depends on the design of the application board and the choice of the external components.
Values down to -70 dBm can be achieved with careful design.
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XE1203F
4
GENERAL DESCRIPTION
The XE1203F is a direct conversion (Zero-IF) half-duplex data transceiver. The circuit operates in three different
ISM frequency bands (433 MHz, 868 MHz and 915 MHz) and uses 2-level FSK modulation/demodulation to provide
a complete transmission link. It is capable of operating at data rates between 1.2 and 152.3 kbit/s, making it ideally
suited for applications where high data rates are required. It also supports the Konnex standard where the bit rate is
32.7 kbit/s. The device includes dedicated Barker encoder/decoder hardware that may be activated to
modulate/demodulate the transmitted signal to reduce in-band interferences.
The XE1203F is a highly programmable device – channel, bit rate, frequency deviation, output power, base band
filter bandwidth, sensitivity vs. linearity, RSSI feature, and many other parameters – which makes it extremely
flexible, to meet a large number of end user requirements.
The main functional blocks of the XE1203F are the receiver, the transmitter, the frequency synthesizer and some
service blocks. The device also includes a series of configuration and status registers. In a typical application, the
XE1203F is programmed by a microcontroller via the 3-wire serial bus SI, SO, SCK to write to and read from these
registers.
The Receiver converts the incoming 2-level FSK modulated signal into a synchronized bit stream.
The Transmitter performs the modulation of the carrier by an input bit stream and the transmission of the
modulated signal.
The Frequency Synthesizer generates the local oscillator (LO) signal for the receiver section as well as the
continuous phase FSK modulated signal for the transmitter section.
The Service Blocks provide the internal voltage and current sources and provide all the necessary functions for the
circuit to work properly.
The Configuration Registers are a set of variable-length registers that are used to store various settings to
operate the XE1203F transceiver circuit. They are listed below in Table 4. Refer to Section 5.2 for the detailed
descriptions of these registers. These registers are accessed in write or read mode through the 3-wire serial bus, as
described in Section 5.1.
Name
Description
ConfigSwitch
RTParam
FSParam
SWParam
DataOut
ADParam
Pattern
1-bit data to switch between 2 sets of user-predefined SWParam Configuration Registers
Receiver and transmitter parameters
LO, Bitrate, Deviation and other frequency parameters
2 sets of user-predefined configuration registers
Status register which can be read through the 3-wire serial interface
Additional parameters
Reference pattern for the “pattern recognition” feature
Table 4: Configuration Registers
Naming convention: throughout this document, each individual bit in a particular Configuration Register includes the
name of this register followed by a bit identifier. For example, RTParam_Band are the “Band” bits within the
RTParam register.
The Digital Interface provides internal control signals for the whole circuit according to the configuration register
settings.
4.1
THE RECEIVER SECTION
The receiver converts the incoming 2-level FSK modulated signal into a synchronized bit stream. The receiver is
composed of a low-noise amplifier, two down-conversion mixers, two base band filters, two base band amplifiers,
two limiters, a demodulator and a bit synchronizer. The bit synchronizer translates the output of the demodulator
into a glitch-free bit stream available on the pin DATA. It also generates a synchronized clock, DCLK, which can be
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7
XE1203F
used to sample the DATA signal without additional external signal processing. In addition, the receiver includes a
digital Received Signal Strength Indicator (RSSI), a Frequency Error Indicator (FEI) that provides information about
the local oscillator frequency error, and a pattern recognition function to detect preprogrammed sequences in the
received serial data stream. Finally, a user-selectable Barker coding/decoding feature can be activated to spread
the outgoing data with an 11-bit Barker code upon transmission and decode the incoming data upon reception by
correlating the spread data with the 11-bit Barker code.
4.1.1
LNA & Receiver modes
The LNA of the receiver has two programmable operation modes: the high sensitivity mode, Mode A, for reception
of weak signals; and the high linearity mode, Modxe B, for strong signals. The operation mode is defined by the
contents of the SWParam_Rmode1 and SWParam_Rmode2 Configuration Register bits.
•
•
4.1.2
Mode A: High sensitivity mode, approximately 13dB better than in Mode B (see 3.2.2, RFS parameter)
Mode B: High Linearity mode, IIP3 approximately 15dB higher than in Mode A (see 3.2.2, IIP3 parameter)
Demodulation chain
The demodulation chain consists of an FSK demodulator, bit synchronizer, Barker decoder and a Pattern
Recognition block. Figure 2 below illustrates the interaction between each section of the demodulation chain.
RTParam_Barker
pow
BARKER
DECODER
data
dclk
FSK
DEMODULATOR
DATA
CONTROL
data
data
dclk
RTParam_Bitsync
pow
BIT
SYNCHRONIZER
data
dclk
FSParam_BR
RTParam_Pattern
pow
PATTERN
RECOGNIZER
pattern
ADParam_Pattern
ADParam_Psize
ADParam_Ptol
Figure 2: Demodulation architecture
4.1.3 Demodulator
The demodulator provides a demodulated data stream from the received FSK modulated base band limited signals,
I_lim and Q_lim. If the end-user application requires direct access to the output of the demodulator, then the
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XE1203F
RTParam_Bitsync and RTParam_Barker Configuration Register bits are set low (disabled). In this case the
demodulator output is directly connected to the DATA pin and the DCLK pin is set to low. Otherwise, the
demodulator output is processed by the bit synchronizer.
For correct operation of the demodulator the modulation index β of the input signal should meet the following
condition:
2 ⋅ ∆f
β=
≥ 2,
BR
where ∆f is the frequency deviation and BR the bit rate.
4.1.4 Bit synchronizer
The raw output signal from the demodulator usually contains jitter and glitches. The bit synchronizer transforms the
data output of the demodulator into a glitch-free bit stream available on the DATA pin and generates a synchronized
clock DCLK to be used for sampling the DATA output (see Figure 3, below).
DATA
(NRZ)
DCLK
Figure 3: Bit synchronizer timing diagram.
To ensure the correct operation of the bit synchronizer, in addition to the requirement for the modulation index
defined in 4.1.3 above, the following conditions have to be satisfied:
•
•
•
•
A preamble of 24 bits is required for the synchronization,
The preamble must be a sequence of “0” and “1” sent alternatively,
During transmission of data, the bit stream must have at least one transition from “0” to “1” or from “1” to “0”
every 8 bits.
The accuracy of the bit rate must be better than ± 5%.
The bit synchronizer is enabled when RTParam_Bsync Configuration Register bit is high. If this bit set low, the bit
synchronizer is disabled. In this case the output of the demodulator is directed to the DATA pin and the DCLK
output is set to “0”.
The received bit rate is defined by the value of the FSParam_BR Configuration Register, and is calculated as
follows:
Bit rate =
152.34e3
int(FSParam_BR(6 : 0)) + 1
where int(x) is the integer value of the unsigned binary representation of (x).
Note: for Konnex standard operations, the bit rate is fixed at 32.7 kbit/s. ADParam_enable_konnex should be set to
a ‘1’.
4.1.5 The DATA and DATAIN pins
The pin DATA is by default used by both the transmitter and the receiver sections. By default it is set as a
bidirectional I/O pin. When in receive mode, demodulated data appears at DATA as an output signal. In transmit
mode, the transmitted bit stream is applied to this pin as an input.
Some applications may require separate input and output pins for the transmitted and received data. In this case
the user has to set the ADParam_disable_data_bidir Configuration Register bit to ‘1’. As a result the DATA pin is set
as an output only for the received data, while the transmit data is controlled via the DATAIN input pin.
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XE1203F
4.1.6 Pattern recognition block
When in receiver mode, this feature is activated by setting RTParam_Pattern Configuration Register bit high. The
demodulated data signal is compared with a pattern stored in the PATParam_Pattern Configuration Register. The
PATTERN output pin is driven by the output of this comparator and is synchronized by DCLK. It is set to high when
a matching condition is detected, otherwise set to low. The PATTERN output is updated at the rising edge of DCLK.
The number of bits used for comparison is defined in the ADParam_Psize Configuration Register and the number of
tolerated errors for the pattern recognition is defined in the ADParam_Ptol register. Figure 4, below, illustrates the
pattern matching process.
Figure 4: Pattern Matching Operation.
4.1.7 RSSI
When enabled, this function provides a Received Signal Strength Indication based on the signal at the output of the
base-band filter. To enable the RSSI function, the RTParam_RSSI Configuration Register bit should be set to “1”.
When enabled, the status of the RSSI in the DataOut_RSSI register is a 2-bit word which can be read via the serial
control interface. The content of the register is defined in Table 5, below, where VRFFIL is the differential amplitude
equivalent to the RF input signal with the receiver operated in A-mode. The thresholds, VTH are the equivalent of the
signal at the output of the base-band filter stage, divided by the signal gain.
DataOut_RSSI
00
Description
VRFFIL ≤ VTHR1
01
VTHR1 < VRFFIL ≤ VTHR2
10
VTHR2 < VRFFIL ≤ VTHR3
11
VTHR3 < VRFFIL
Table 5 RSSI status description
Two possible ranges, each having a set of three VTH threshold values, VTHR1, VTHR2, and VTHR3 (see 3.2.2 for
actual values), are selected with the RTParam_RSSIR Configuration Register bit. They provide an overall RSSI
range of typically 25 dB.
The timing diagram of an RSSI measurement is illustrated in the Figure 5 below. When the RSSI function has been
activated, the signal strength is periodically measured and the result is stored in the register DataOut_RSSI each
time this DataOut_RSSI register is read via the 3-wire serial interface. Note that TS_RS is the wake-up time
required after the function has been enabled to ensure that a valid reading of RSSI is obtained.
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10
XE1203F
RTParam_Rssi
/en
TS_RSSI
rssi_out
xxx
TS_RSSIM
val1
val2
val3
val4
val5
0
saout_rssi
dataout_rssi
xxx
val1
val4
Figure 5: RSSI measurement timing diagram
Note on the Dataout_RSSI update: during a read sequence of the Dataout_RSSI Status Register, the Saout_rssi
signal is generated internally as illustrated in the Figure 6 below. It can be seen the value of the Dataout_RSSI
Status Register is updated upon transmission of the bit A0 on the SI line. The maximum frequency of SCK during
the read operation of the RSSI value is 100 kHz.
A(4) A(3)
SI
A(2) A(1) A(0)
EN
SO
HZ
D(7) D(6) D(5)
D(4) D(3)
D(2) D(1)
D(0)
HZ
SCK
saout_rssi
Figure 6: Generation of saout_rssi
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XE1203F
4.1.8 Frequency Error Indicator – FEI
When enabled this function provides an indication of the frequency error of the local oscillator compared with the
received carrier frequency. For guaranteed operation of the FEI function the following two conditions should be met:
1) The modulation index, β, should meet the following condition:
2 ⋅ ∆f
β=
≥ 2,
BR
where: ∆f = frequency deviation of the modulated input signal, BR = input data bit-rate.
2) The bandwidth of the baseband filter (BBW) must be greater than the sum of the frequency offset and the
received peak signal bandwidth, as defined below:
BBW > fOFFSET + BWSIGNAL
where BBW is the baseband filter bandwidth defined by the RTParam_BW register. fOFFSET is the difference
 BR

between the carrier frequency and the LO frequency, and BW SIGNALis equal to 
+ ∆f  .
 2

Note on the timing for FEI measurement: The timing diagram of the FEI measurement process is illustrated in
Figure 7 below. As long as the FEI function remains enabled, the frequency error is continuously measured every
2/BR seconds, starting TS_FEI (see Paragraph 3.2.2) after the FEI function is enabled. The measurement results
are loaded into the status registers Dataout_MSB_fei and Dataout_LSB_fei each time the Dataout_LSB_fei register
is read through the 3-wire serial interface. In the diagram below, Saout_fei is generated internally during a read
sequence from the “Dataout_LSB_fei ‘’ status register.
RTParam_FEI
EN
2/BR
TS_FEI
fei_out
first
evaluation
val0
val1
val2
val3
val4
0
saout_fei
Dataout_MSB_fei&
xxx
val1
Dataout_LSB_fei
val3
Figure 7: Timing diagram of the FEI measurement process
The maximum frequency of SCK during the FEI read operation is 100 kHz. When using the Konnex standard, the
bit ADParam_enable_konnex Configuration Register must be set to ‘1’.
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The frequency error can then be calculated by using the following formula:
Frequency error = (BR/8)*int(Dataout_FEI(11:0)),
where Dataout_FEI(11:0) = Dataout_MSB_fei(3:0) + Dataout_LSB_fei(7:0), and int(x) is the integer value of the
signed binary representation of x.
4.2
THE TRANSMITTER SECTION
The Transmitter performs the modulation of the carrier by an input bit stream and the transmission of the modulated
signal. Carrier modulation is achieved directly through the frequency synthesizer via a Sigma-Delta modulator. The
frequency deviation and the bit-rate of the modulated carrier are programmable. An on-chip power amplifier then
amplifies the RF signal. The output power can be programmed with 4 possible settings:
RTParam_Tpow
Output power
00
RFOP1
01
RFOP2
10
RFOP3
11
RFOP4
Table 6: Output power settings
4.2.1 Transmitter
The transmit data should be applied to DATA or DATAIN pins depending on the setting of the
ADParam_disable_data_bidir configuration bit. If the parameter is set to “1”, then the DATAIN pin is used, otherwise
the bidirectional pin DATA is used.
The modulating signal on DATA or DATAIN can be pre-processed before modulating the local oscillator to produce
the outgoing FSK RF signal. This is the pre-filtering feature. The pre-filtering is selected by setting the
RTParam_Filter configuration bit to “1”. When RTParam_Filter is set to “1”, the input baseband data is pre-filtered
before being applied to the frequency synthesizer. This means that the rising and falling edge of each bit is linearly
smoothed with a staircase transition. When RTParam_Filter is set to “0”, the input baseband data is applied directly
to the frequency synthesizer without any pre-filtering function.
The two possible modulation methods are shown in Figure 8, where “datain” is the input bit stream from DATA or
DATAIN pins.
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XE1203F
Datain or
data
No filtering
INfreq_synth
Staircase filtering
INfreq_synth
Figure 8: Modulation with and without pre-filtering
The main characteristic of this pre-filtering function is the ratio between the rise/fall time to the bit duration, trise/tbit.
The value of this ratio can be programmed between two pre-defined values in the RTParam_Stair configuration bit,
as shown in the Table 7.
RTParam_Stair
trise/tbit
0
1
10%
20%
Table 7: trise/tbit ratio
When the pre-filtering function is enabled (RTParam_Filter set to “1”), only the following bit rates and frequency
deviations can be used:
FSParam_Dev
Frequency deviation
00101000
00110111
01010000
10100000
11001000
40 kHz
55 kHz
80 kHz
160 kHz
200 kHz
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XE1203F
FSParam_Br
Bit rate (bit/s)
1111110
0111111
0011111
0001111
0000111
0000011
0000001
others (*)
1200
2400
4800
9600
19200
38400
76800
153000
Table 8: Possible bit rates and frequency deviations when pre-filtering is enabled
(*) For any programmed value of FSParam_Br which is not in the Table 8 above, the data-rate is fixed to 153 kbit/s
and the pre-filtering is applied as defined by the user.
If ADParam_enable_konex is set high, then the pre-filtering option is available for a bit rate of 32.7 kbit/s and one of
the frequency deviations defined above.
4.2.2 Barker encoder/decoder
The Barker encoder/decoder hardware can be activated to modulate/demodulate the transmitted signal to reduce
in-band interferences The Barker decoder provides an alternative to the bit synchronizer only for a fixed data rate
of 1154bits/s. The Barker block is selected when the RTParam_Barker configuration bit is set to “1”. In
transmission, the information data at a bit rate of 1154bits/s is spread using an 11-bit Barker code. The result is an
encoded bit stream at 12.7 kilochips per second (kcps), which is applied to the frequency synthesizer. On the
receiver part, the signal is demodulated using the FSK demodulator (at 12.7 kcps) and then fed into the Barker
decoder to recover the un-encoded data at 1154 bit/s, together with a synchronized clock to sample it. Figure 8 on
the next page, illustrates the coding/decoding process.
Figure 9: Barker Encoding and Decoding Channels.
In receiver mode, the XE1203F provides a clock output, DCLK, to a microcontroller. The data can be sampled at
the rising edge of the clock. When using the Barker decoding process, DCLK is used to detect the sync acquisition.
If there is no valid data, DCLK remains high. The first falling edge of the clock means that the sync acquisition
phase has been reached and that the output data is now available. This is illustrated below in Figure 10.
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XE1203F
Figure 10: Data exchange during reception mode with Barker the feature enabled
When using the Barker encoding in transmitter mode, the RTParam_Barker parameter is set to “1” and the
baseband data at 1154 bit/s is applied through either the DATA or DATAIN depending to the status of
ADParam_disable_data_bidir. The data is spread into an encoded chip stream at 12.7 kcps by the Barker encoder.
This chip stream is directly applied to the frequency synthesizer without any pre-filtering.
When using the Barker coder/decoder feature in transmission mode, the DCLK pin is used to synchronize the data
coming from a microcontroller or another source. This DCLK clock is generated by the XE1203F. At the falling edge
of the each clock a new data bit (on DATA or DATAIN) should be supplied by the microcontroller or another source.
This data is sampled by the XE1203F at the next rising edge of DCLK. It is then spread by using an 11-bit length
Barker code. The Figure 11 shows the data exchange during the transmission mode when the Barker feature is
enabled.
dclk
@1154 Hz
information data
from a microcontroller
bit rate = 1154 bps
bit0
bit1
bit2
bit3
bit4
bit5
bit6
Spread data
@12.7 Kchps
spread
bit0
spread
bit1
spread
bit2
spread
bit3
spread
bit4
spread
bit5
Figure 11: Data exchange during transmission mode with the Barker feature enabled
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XE1203F
4.3
THE FREQUENCY SYNTHESIZER
The Frequency Synthesizer generates the local oscillator (LO) signal for the receiver section as well as the
continuous phase FSK (CPFSK) modulated signal for the transmitter section. The core of the synthesizer is
implemented with a Sigma-Delta PLL architecture. The frequency is programmable with a minimum step-size of 500
Hz in the 433, 868 and 915 MHz frequency bands. This block includes a crystal oscillator which provides the
frequency reference for the PLL. This reference frequency can also be used as a reference clock for the external
microcontroller on the CLKOUT pin.
4.3.1 Clock Output for external processor
A reference clock can be generated by XE1203F for use by an external microcontroller. The RTParam_Clkout
configuration bit determines the status of the CLKOUT pin. When set high CLKOUT is enabled, otherwise it’s
disabled. The output frequency at CLKOUT is defined by the value of the ADParam_Clkfreq parameter. The output
frequency at CLKOUT is the reference oscillator frequency divided by 4, 8, 16 or 32. With the reference oscillator
frequency at 39 MHz this provides a reference clock at 9.75 MHz, 4.87 MHz, 2.44 MHz or 1.22 MHz, respectively.
This clock signal is disabled in Sleep Mode.
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XE1203F
5
SERIAL INTERFACE DEFINITION AND PRINCIPLES OF OPERATION
5.1
SERIAL CONTROL INTERFACE
A 3-wire bi-directional bus (SCK, SI, SO) is used to communicate with the XE1203F. SCK and SI are input signals
supplied externally, for example by the microcontroller. The XE1203F configures the SO signal as an output pin
during read operation, and it is tri-stated in other modes. The falling edge of the SCK signal is used to sample the SI
pin to write data into the internal shift register of the XE1203F. The rising edge of the SCK signal is used to output
data to SO pin by XE1203F, so the microcontroller should sample data at the falling edge of SCK.
The signal EN must be low during the whole write and read sequences. In write mode the content of the particular
configuration register (see 5.2) is updated on the next rising edge of the EN signal. Before this rising edge, the new
data is stored in temporary registers which do not affect the transceiver settings.
The timing diagram of a write sequence is illustrated in Figure 12 below. The sequence is initiated when a Start
condition is detected, defined by the SI signal being set to “0” during one period of SCK. The next bit is a read/write
(R/W) bit which should be “0” to indicate a write operation. The next 5 bits contain the address of the
configuration/status registers A[4:0] to be accessed, MSB first (see 5.2). Then, the next 8 bits contain the data to be
written into the register. The sequence ends with 2 stop bits set to “1”. The data on SI should change on the rising
edges of SCK, and is sampled on the falling edge of SCK. After the 2 stop bits, the data transfer is terminated. The
SI line should be at “1” for at least one extra SCK clock cycle before a new write or read sequence can start. This
mode of operation allows data to be written into multiple registers keeping the EN line low.
The maximum frequency of SCK is 1 MHz, except as defined above when reading the RSSI or FEI outputs, where
the maximum frequency of SCK is limited to 100 kHz. The minimum clock pulse width is 0.5 us. Over the operating
supply and temperature range, set-up and hold time for SI on the falling edge of SCK are 200 ns.
The register at address 0 is one bit long. When writing this register, the sequence described above is valid except
that only one data bit is required instead of 8. However, if a single write procedure is used for all registers 8 data bits
must be sent when writing at address 0, but only the MSB will be stored at address 0. The remaining 7 data bits
must all be “1”.
sck
si
A(4) A(3) A(2) A(1) A(0) D(7) D(6) D(5)
D(4) D(3)
D(2) D(1) D(0)
/en
so
High impedance
Figure 12: Write sequence into configuration register
Figure 13 illustrates a write sequence at address zero.
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XE1203F
sck
A(4)
si
A(3)
A(2)
A(1)
A(0)
D(7)
/en
so
High impedance
Figure 13: Write sequence into configuration register at address zero
The time diagram of a read sequence is illustrated in Figure 14 below. The sequence is initiated when a Start
condition is detected, defined by the SI signal being set to “0” during a period of SCK. The next bit is a read/write
(R/W) bit which should be “1” to indicate a read operation. The next 5 bits are the address of the control register
A[4:0] to be accessed, MSB first. The data from the register is then output on the SO pin. The data become valid at
the rising edges of SCK and should be sampled at the falling edge of SCK. After this, the data transfer is
terminated. The SI line must stay high for at least one extra SCK clock cycle to start a new write or read sequence.
The maximum current drive on SO is 2 mA at a supply voltage of 2.7V and the maximum load is CLop, as defined
in Paragraph 3.2.2.
When the serial interface is not used for read or write operations, both SCK and SI should be set to “1”. Except
when in read mode, SO is set to a high impedance mode.
sck
A(4) A(3) A(2) A(1)
si
A(0)
/en
so
High impedance
D(7) D(6) D(5)
D(4) D(3)
D(2) D(1)
D(0) High impedance
Figure 14: Read sequence of configuration register
When reading the register at address zero, the timing diagram is illustrated in Figure 15.
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XE1203F
sck
A(4)
si
A(3)
A(2)
A(1)
A(0)
/en
so
D(7)
High impedance
High impedance
Figure 15: Read sequence of configuration register at address 0
5.2
CONFIGURATION AND STATUS REGISTERS
The XE1203F has several operating modes and configuration parameters which can be programmed by the user or
the application. In addition, status information may be read from the circuit. Some of the operating modes, the
status information and the configuration parameters are stored in a series of internal Configuration and Status
Registers that can be accessed by the microcontroller through the 3-wire serial interface.
There are seven variable Configuration and Status Registers, as listed below in Table 9.
Name
Description
Size
(bits)
1x1
Address
(binary format)
00000
ConfigSwitch
1-bit data to switch between 2 sets of
user-predefined
SWParam
Configuration Registers
RTParam
Receiver and transmitter parameters
2x8
00001 - 00010
FSParam
LO, Bitrate, Deviation
frequency parameters
other
3x8
00011 - 00101
SWParam
2 sets of user-predefined configuration
registers
6x8
00110 - 01011
DataOut
Status register which can be read
through the 3-wire serial interface
2x8
01100 - 01101
ADParam
Additional parameters
5x8
01110 - 10010
Pattern
Reference pattern
recognition” feature
4x8
10011 - 10110
for
and
the
“pattern
Table 9: Configuration and Status Registers List
All the bits that are referred to as “reserved” in this section should be set to “0” during write operations.
5.2.1 The ConfigSwitch Register
When operating the XE1203F, it might by useful to quickly switch between two pre-defined operating modes, to
save time and traffic on the 3-wire serial interface bus. This may occur when the XE1203F is required to switch
quickly between receive and transmit mode, when it has to operate on two different carrier frequencies, or when it
has to switch between the high linearity mode B and the high sensitivity mode A. For that purpose, the five
parameters stored in the SWParam Configuration Register are duplicated: the configuration set#1 and the
configuration set #2.
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Depending on the ConfigSwitch 1-bit Register or the input level at the SWITCH pin, the XE1203F transceiver will
use either the SWParam configuration set#1 or the set #2. If the RTParam_Switch_ext configuration parameter is
low, then the SWParam configuration set is selected by the ConfigSwitch parameter – set#1 if ConfigSwitch is “0”,
set#2 if ConfigSwitch is “1”. If the RTParam_Switch_ext configuration parameter is high, then the SWParam
configuration set is selected by the SWITCH pin – set#1 if SWITCH is low, set#2 if SWITCH is high.
Table 10 below summarizes the chip configuration programming:
ConfigSwitch
Register
0
SWITCH pin
SWITCH is an output:
RTParam_switch_ext
configuration parameter
0
SWParam_mode_1
SWParam_Power_1
SWParam_Rmode_1
SWParam_t_delsig_in_1
SWParam_freq_1
‘1’ in transmitter mode
‘0’ in the other modes
1
SWITCH is an output:
0
Set #2:
SWParam_mode_2
SWParam_Power_2
SWParam_Rmode_2
SWParam_t_delsig_in_2
SWParam_freq_2
‘1’ in transmitter mode
‘0’ in the other modes
X
SWParam configuration
set selected
Set #1:
0
1
Set #1:
SWParam_mode_1
SWParam_Power_1
SWParam_Rmode_1
SWParam_t_delsig_in_1
SWParam_freq_1
X
1
1
Set #2:
SWParam_mode_2
SWParam_Power_2
SWParam_Rmode_2
SWParam_t_delsig_in_2
SWParam_freq_2
Table 10: ConfigSwitch, SWITCH pin and SWParam Configuration Register
By default the configuration set#1 is used and register RTParam_switch_ext is set to ‘0’.
Note that a new value of the ConfigSwitch register or at the SWITCH pin should be modified when the EN signal is
low. The actual switch to the newly selected set of SWParam register will be applied to the transceiver on the next
rising edge of the EN signal.
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5.2.2 RTParam Configuration Register
Receiver and transmitter parameters
Name
Bits
Address
RTParam_Bitsync
7
00001
Description
Bit synchronizer
0 -> disabled
1 -> enabled
RTParam_Barker
6
00001
BARKER coder/decoder:
0 -> disabled
1 -> enabled
RTParam_Rssi
5
00001
RSSI function:
0 -> disabled
1 -> enabled
RTParam_Rssir
4
00001
RSSI range:
0 -> low range (see 3.2.2)
1 -> high range (see 3.2.2)
RTParam_Fei
3
00001
FEI function:
0 -> disabled
1-> enabled
RTParam_BW
2
00001
Baseband filter bandwidth (BBW)
0 -> 200 kHz (DSB)
1 -> 600 kHz (DSB)
RTParam_Osc
1
00001
Reference frequency source:
0 -> internal crystal oscillator
1 -> external source
RTParam_Clkout
0
00001
CLKOUT - Reference frequency divided by 4,8,16,or 32:
0 -> disabled
1 -> enabled
RTParam_Stair
7
00010
Transmitter pre-filter rise/fall time:
0 -> 10% of bit duration
1 -> 20% of bit duration
RTParam_Filter
6
00010
Pre-filtering of the bit stream in transmitter mode
0 -> no filtering
1 -> filtering
The filtering function is available only for the following bit rates
and frequency deviations:
FSPanam_Br = "1111110" -> BR = 1200 bit/s
FSPanam_Br = "0111111" -> BR = 2400 bit/s
FSPanam_Br = "0011111" -> BR = 4800 bit/s
FSPanam_Br = "0001111" -> BR = 9600 bit/s
FSPanam_Br = "0000111" -> BR = 19200 bit/s
FSPanam_Br = "0000011" -> BR = 38400 bit/s
FSPanam_Br = "0000001" -> BR = 76800 bit/s
FSParam_Dev = "00101000" -> ∆f = 40 kHz
FSParam_Dev = "00110111" -> ∆f = 55 kHz
FSParam_Dev = "01010000" -> ∆f = 80 kHz
FSParam_Dev = "10100000" -> ∆f = 160 kHz
FSParam_Dev = "11001000" -> ∆f = 200 kHz
RTParam_Modul
5
00010
Transmitter modulation:
0 -> enabled
1 -> disabled
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Name
Bits
Address
RTParam_IQAMP
4
00010
Description
I&Q amplifiers:
0 -> disabled
1 -> enabled
RTParam_Switch_ext
3
00010
SWParam configuration set selection:
0 -> configuration set defined by ConfigSwitch. SWITCH is an
output
1 -> configuration set defined by the pin SWITCH. SWITCH is
an input
RTParam_Pattern
2
00010
Pattern recognition function:
0 -> disabled
1 -> enabled
RTParam_Band
1-0
00010
Frequency band:
01 -> 433 – 435 MHz
10 -> 868 – 870 MHz
11 -> 902 – 928 MHz
Table 11: RTParam Configuration Register
5.2.3 FSParam Configuration Register
LO, Bitrate, Deviation and other frequency parameters
Name
Bits
Address
FSParam_Dev
7-0
00011
Description
Frequency deviation ∆f:
∆f =int( FSParan_Dev) * 1 kHz,
where int(x) = integer value of the binary representation of x.
Example:
00000001 -> ∆f = 1 kHz
11111111 -> ∆f = 255 kHz
FSParam_Change_Osr
7
00100
OSR Mode (Oversampling Rate mode):
0 -> default Bit rate defined by FSParam_Br
1 -> variable OSR
FSParam_Br
6-0
00100
Bit rate (when "FSParam_Change_Osr” = “0”):
Br = 152340/(int(FSParam_Br)+1),
where int(x) = integer value of the binary representation of x.
Example:
0000000 -> Br = 152.34 kbit/s
1111111 -> Br = 1.19 kbit/s
0000100 -> Br = 32.7 kbit/s used in Konnex mode
FSParam_OSR
7-0
00101
Define BR in terms of FSParam_BR and FS_Param_OSR:
FSParam_OSR = “00011101” and FSParam_Change_Osr =
‘1’ for Konnex standard
Table 12: FSParam Configuration Register
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5.2.4 SWParam Configuration Register - switching parameters
The table below shows 2 sets of user-predefined configuration registers. Please refer to Section 5.2 for more
details.
Name
Bits
Address
SWParam_mode_1
7-6
00110
Description
Chip mode configuration set#1:
00 -> Sleep mode
01 -> Stand by mode
10 -> Receiver mode
11 -> Transmitter mode
SWParam_Power_1
5-4
00110
Transmitter output power configuration set#1:
00 -> 0 dBm
01 -> 5 dBm
10 -> 10 dBm
11 -> 15 dBm
SWParam_Rmode_1
3
00110
Receiver Mode configuration set#1:
0 -> Mode A (high sensitivity)
1 -> Mode B (high linearity)
RESERVED
2-0
00110
RESERVED
SWParam_Freq_1
7-0
00111
7-0
01000
LO frequency in 2’s complement representation configuration
set#1:
00…0 -> Flo = middle of the range
0X…X-> Flo = higher than the middle of the range
1X…X-> Flo = lower than the middle of the range
see Table 14 below
SWParam_node_2
7-6
01001
Chip mode configuration set#2:
00 -> Sleep mode
01 -> Stand by mode
10 -> RX mode
11 -> TX mode
SWParam_Power_2
5-4
01001
Transmitter output power configuration set#2:
00 -> 0 dBm
01 -> 5 dBm
10 -> 10 dBm
11 -> 15 dBm
SWParam_Rmode_2
3
010001
Receiver Mode configuration set#2:
0 -> Mode A (high sensitivity)
1 -> Mode B (high linearity)
RESERVED
2-0
01001
RESERVED
SWParam_Freq_2
7-0
01010
7-0
01011
LO frequency in 2’s complement representation configuration
set#2:
00…0 -> Flo = middle of the range
0X…X-> Flo = higher than the middle of the range
1X…X-> Flo = lower than the middle of the range
see Table 14 below
Table 13: SWParam Configuration Register
The table following provides examples of LO frequency settings with FSParam_Freq:
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SWParam_Freq_1 MSB (Byte
address 00111)
SWParam_Freq_1 LSB
(Byte address 01000)
or
or
SWParam_Freq_2 MSB (Byte
address 01010)
SWParam_Freq_1 LSB
(Byte address 01011)
Bit 7
Bit 0
Bit 7
Resulting LO setting
Note: reference frequency = 39.0 MHz
Bit 0
00000000
00000000
F0, where F0 depends on the selected frequency
band (see RTParam_Band )
F0 = 434.0 MHz for the 433-435 MHz band
F0 = 869.0 MHz for the 868-870 MHz band
F0 = 915.0 MHz for the 902-928 MHz band
00000000
00000001
F0 + 500 Hz
00000000
00000010
F0 + 2 * 500 Hz
11111111
11111111
F0 – 500 Hz
11111111
11111110
F0 – 2 * 500 Hz
Table 14: Examples of LO frequency settings
5.2.5 DataOut Status Register
Status register which can be read through the 3-wire serial interface
Description
Name
Bits
Address
DataOut_Rssi
7-6
01100
RSSI output:
0 0 -> lowest level, ≤VTHR1
nd
0 1 -> 2 level, VTHR1<RSSI level≤VTHR2
rd
1 0 -> 3 level, VTHR2<RSSI level≤VTHR3
1 1 -> highest level, VTHR3<RSSI level
RESERVED
5-4
01100
RESERVED
DataOut_MSB_fei
3-0
01100
Fei output (MSB)
DataOut_LSB_fei
7-0
01101
Fei output (LSB)
Ferror = (Br/8)*int(DataOut_MSB_fei & DataOut_LSB_fei)
Where int(x) = integer value of the binary representation of x
Table 15: DataOut Status Register
5.2.6 ADParam Configuration Register
Additional parameters
Name
Bits
Address
ADParam_Psize
7-6
01110
Description
Size of reference pattern recognition word:
0 0 -> 8 bits
0 1 -> 16 bits
1 0 -> 24 bits
1 1 -> 32 bits
ADParam_Ptol
5-4
01110
Number of tolerated errors for the pattern recognition:
00 -> 0 error
01 -> 1 error
10 -> 2 errors
11 -> 3 errors
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Name
Bits
Address
ADParam_Clk_freq
3-2
01110
Description
CLKOUT frequency (if enabled)
00 -> 1.22 MHz (div ratio :32)
01 -> 2.44 MHz (div ratio :16)
10 -> 4.87 MHz (div ratio :8)
11 -> 9.75 MHz (div ratio :4)
ADParam_Invert
1
01110
Inversion of Rx output data:
0 -> disabled
1 -> enabled
ADParam_RegBW
0
01110
Baseband filter bandwidth calibration:
0 -> enabled
1 -> disabled
ADParam_Regfreq
7
01111
Period of baseband filter bandwidth calibration whilst Rx
enabled:
0 -> only at start-up of the receiver
1 -> 60 seconds (default mode) or 7 seconds (test mode)
ADParam_Regcond
6
01111
Baseband filter bandwidth calibration as a function of selected
bandwidth:
0 -> calibration restarted each time the bandwidth is changed
1 -> no calibration when the bandwidth is changed
ADParam_Xsel
5
01111
Selection of the XOSC load capacitance mode:
0 -> CL+C0 = 15 pF
1 -> CL+C0 = 11 pF, low current mode
ADParam_Resxosc
4-1
01111
Selection of the value of the shunt resistor across ports TKA
and TKB for a third overtone XTAL operation:
0000 -> 3800 kΩ
0010 -> 4.65 kΩ
0100 -> 8.79 kΩ
0110 -> 3.22 kΩ
1000 -> 16.55 kΩ
1010 -> 3.79 kΩ
1100 -> 6.04 kΩ
1110 -> 2.81 kΩ
ADParam_enable_konnex
0
01111
0001 -> 2.55 kΩ
0011 -> 1.78 kΩ
0101 -> 2.07 kΩ
0111 -> 1.56 kΩ
1001 -> 2.26 kΩ
1011 -> 1.66 kΩ
1101 -> 1.91 kΩ
1111 -> 1.48 kΩ
Konnex mode:
0 -> disabled
1 -> enabled
ADParam_Chge_thres
7
10000
Enable programming of the sync and acquisition thresholds:
0 -> threshold are hard-coded and sync-loss counter is 50 bits
1 -> threshold are defined by BParam_Sync_thres and
BParam_Trac_thres
Sync loss counter is variable and defined by
ADParam_Sync_loss
ADParam_Sync_thres
6:0
10000
Barker mode sync acquisition threshold
ADParam_disable_data_bidir
7
10001
DATA port bidirectional mode:
0 -> enabled
1 -> disabled: DATA = output, DATAIN = input
ADParam_Trac_thres
6-0
10001
Threshold for tracking Barker mode
ADParam_Fix_bsync
7
10010
bit synchronizer configuration:
0-> default configuration
1-> high-interference environment
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XE1203F
Name
Bits
Address
ADParam_Sync_loss
6-0
10010
Description
Number of bits before sync loss detection for Barker decoding
algorithm
Table 16: ADParam Configuration Register
5.2.7 Pattern register
This register holds the user supplied reference pattern of 8, 16, 24, or 32 bits (see the ADParam_Psize parameter).
nd
The first byte of this pattern is always stored in the byte at address A[4:0] = 10011. If used, the 2 byte is stored at
rd
th
address A[4:0] = 10100, the 3 byte at address A[4:0] = 10101, and finally the 4 byte at address A[4:0] = 01011.
The MSB bit of the reference pattern is always bit 7 of address 10011.
Comparing the demodulated data, the first bit received of the last word is compared with bit 7 (the MSB) of byte
address 10011. The last bit received is compared with bit 0 (the LSB) in the Pattern register.
Name
Bits
Byte Address
PATParam_Pattern
7-0
10011
10100
10101
10110
Description
st
1 byte of the reference pattern
nd
2 byte
rd
3 byte
th
4 byte
Table 17: PATParam Pattern Registers
Example of pattern recognition with a 32-bit pattern:
Byte Address
10011
Bit 7
Bit 0
Byte Address
10100
Bit 7
Bit 0
Byte Address
10101
Bit 7
Bit 0
Byte Address
10110
Bit 7
Bit 0
10010011
10101010
10010011
10101010
10010011
10101010
10010011
10101010
101
previous
bits
demodulator
from
last bit received
Figure 16: Example of pattern recognition with a 32-bit pattern
Example of pattern recognition with an 8-bit pattern:
Byte Address
10011
Bit 7
Bit 0
Byte Address
10100
Bit 7
Bit 0
Byte Address
10101
Bit 7
Bit 0
Byte Address
10110
Bit 7
Bit 0
10010011
Xxxxxxxx
Xxxxxxxx
Xxxxxxxx
101
10010011
previous bits from
demodulator
last bit received
Figure 17: Example of pattern recognition with an 8-bit pattern
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XE1203F
5.2.8 Test Registers and additional settings
Some settings in this 9-byte register can be used to have access to additional configurations of the circuit. These
settings are described in the Table 18 below:
Name
Bits
Byte Address
TParam_BW
3
10111
Description
Baseband filter bandwidth (DSB):
0 -> default values defined by
RTParam_BW (200 and 600 kHz)
1 -> 300kHz
TParam_HPF
1-0
10111
SSB cut-off frequency of the HPF stage
(for cancellation of DC and low-frequency
offsets in the baseband circuit):
00 -> 4.3 kHz
01 -> 8.7 kHz
10 -> 17.3 kHz
11 -> 34.6 kHz
Table 18: Test registers and additional settings
5.3
OPERATING MODES
The XE1203F has four main operating modes illustrated in Table 19 below.
These modes are defined by the content of the SWParam_mode_1 parameter when configuration set #1 is
selected, or by the content of the SWParam_mode_2 parameter when configuration set #2 is selected. See also
Section 5.2.1.
Mode
SWParam_mode1(1:0)
SWParam_mode_2(1:0)
Description
Sleep mode
00
-
Standby mode
00
Quartz oscillator enabled
Receiver mode
10
Quartz oscillator, Frequency synthesizer, Receiver enabled
Transmitter mode
11
Quartz oscillator, Frequency synthesizer, Transmitter enabled
Table 19: XE1203F Operating Modes
5.3.1 Standard power up sequence for the receiver and transmitter
The XE1203F circuit can be switched between any configuration by using the 3 wire interface (ConfigSwitch) or by
using the pad SWITCH. This section describes the switching sequence of the chip. Figure 18 shows the transition
sequence from sleep mode to receiver mode via stand by mode.
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XE1203F
SLEEP -> STAND_BY -> RECEIVER
Programmed
mode
SLEEP
STAND_BY
RECEIVER
EN
TS_RE
TS_OS
Actual mode
STAND_BY
SLEEP
RECEIVER
SLEEP -> STAND_BY -> TRANSMITTER
Programmed
mode
SLEEP
STAND_BY
TRANSMITTER
EN
TS_TR
TS_OS
Actual mode
SLEEP
STAND_BY
TRANSMITTER
TRANSMITTER -> RECEIVER
Programmed
mode
TRANSMITTER
RECEIVER
EN
TS_RE
Actual mode
TRANSMITTER
RECEIVER
RECEIVER -> TRANSMITTER
Programmed
mode
RECEIVER
TRANSMITTER
EN
Actual mode
TS_TR
RECEIVER
TRANSMITTER
Figure 18: Mode transition
5.4
SELECTION OF THE REFERENCE FREQUENCY
The reference clock used by the frequency synthesizer and internal digital circuit can be generated internally by
connecting an external crystal between XTA and XTB, or provided by an external oscillator. When using an external
source, the signal should be applied to port XTA and the RTParam_Osc configuration bit should be set to “1”.
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XE1203F
rd
The XE1203F can be used with a 39 MHz crystal operating in fundamental mode or in 3 overtone mode. For third
overtone operation, an internal resistor to be switched across the crystal terminals XTA and XTB is required. This
resistor can be selected by programming the ADParam_Resxosc(3:0) parameter. The required value depends on
the overtone crystal specification.
rd
When using 3 overtone mode, the user should be aware that during its power up the XE1203F oscillator will
attempt to start at the fundamental frequency of the crystal. It will only switch to the overtone mode when properly
programmed through the 3-wire interface bus. As a result, if a microcontroller uses the XE1203F CLKOUT as a
clock source it is advisable to allow the oscillator frequency to settle before undertaking any time or timing sensitive
operations.
For fundamental mode operation, the ADParam_Resxosc(3:0) parameter is set to the default value of ”0000’’. This
switches a 3.8 MΩ resistance across the crystal terminals.
5.5
CLOCK OUTPUT INTERFACE
When register “RTParam_Clkout” is set to “1” , the reference frequency is divided by 4, 8, 16 or 32, depending on
the value of the register “ADParam_Clkfreq”, and provides a reference signal at CLKOUT for a microcontroller or
external circuitry. If the reference frequency is 39 MHz, then the output frequency available at CLKOUT is as
defined in Table 20 below:
ADParam_Clkfreq
CLKOUT frequency
00
1.22 MHz
01
2.44 MHz
10
4.87 MHz
11
9.75 MHz
Table 20: Clock Output Frequency Selection
When the XE1203F is in sleep mode, CLKOUT is disabled even if RTParam_Clkout remains high.
5.6
DEFAULT SETTINGS AT POWER-UP
The internally generated power-on-reset signal sets the RTParam, FSParam, ADParam and Pattern registers to the
00hex value.
There is one important exception for CLKOUT. Although the RTPAram_CLkout is set to ”0” at power-on reset,
meaning the feature should be disabled, the XE1203F will generate a CLKOUT signal after a power-on reset to
provide a clock signal to a possible microcontroller connected to it. After a power-on reset, CLKOUT will be the
lowest available frequency, e.g. 1.22 MHz with a 39 MHz reference frequency. Then, on the first rising edge of the
/EN signal – for example after a programming sequence via the 3-wire interface bus - the content of the
configuration registers will be updated. If the RTParam Configuration Register has not been programmed during
this first sequence after a power-on reset, the CLKOUT clock signal will be disabled. It is strongly advised to
initialize the RTPAram_CLkout parameter appropriately during the first programming sequence after a power-on
reset, especially if an external microcontroller does use this CLKOUT clock signal to operate.
It is recommended to initialize the XE1203F registers immediately after power-up.
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XE1203F
6
APPLICATION INFORMATION
This section provides details of the recommended component values for the frequency dependant blocks of the
XE1203F. Note that these values are dependent upon circuit layout and PCB structure, and that decoupling
components have been omitted for clarity.
6.1
RECEIVER MATCHING NETWORK
The schematic of the matching network at the input of the receiver is given below in Figure 19 (for a source
impedance of 50Ω).
CR1
SOURCE
RFA
XE1203
LR1
CR3
RFB
CR2
Figure 19: Receiver matching network
The typical recommended values for the external components are shown in Table 21:
Name
Typical Value
for 434 MHz
Typical Value
for 868 MHz
Typical Value
for 915 MHz
Tolerance
CR1
1.5 pF
1.5 pF
1.0 pF
± 5%
CR2
1.5 pF
1.2 pF
1.0 pF
± 5%
CR3
NC
NC
NC
± 5%
LR1
100 nH
27 nH
27 nH
±5%
Table 21: Typical component values for the matching network
6.2
TRANSMITTER MATCHING NETWORK
The optimum load impedances for 15 dBm output power at the three main frequencies are shown in Table 22:
PA optimum load
434 MHz
868 MHz
915 MHz
102 – 12j
78 + 19j
83 + 18j
Table 22: Optimum load impedances for 15 dBm output power
The Smith charts in Figure 20, Figure 21, and Figure 22 below show contours of output power versus load
impedance when the highest transmit level is selected, i.e. 15 dBm:
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XE1203F
434 MHz – 15 dBm
1
0.8
1.2
0.6
1.6
2
0.4
3
0.3
0.2
0.1
0
0.1
0.2
0.5
0.3
15 dBm
1.4
1
14 dBm
0.1
0.2
0.3
12 dBm
3
0.4
2
1.6
0.6
0.8
1.2
1
Figure 20: Output power vs. load impedance at 434 MHz
868 MHz – 15 dBm
0.8
1
1.2
0.6
1.6
2
0.4
3
0.3
0.2
0.1
0
15 dBm
0.1
0.2
0.3
0.5
1
1.4
2
14 dBm
0.1
0.2
12 dBm
0.3
3
0.4
2
0.6
1.6
0.8
1.2
1
Figure 21: Output power vs. load impedance at 868 MHz
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XE1203F
915 MHz – 15 dBm
1
0.8
1.2
0.6
1.6
2
0.4
3
0.3
0.2
0.1
15 dBm
0.1
0
0.2
0.3
0.5
1
1.4
2
14 dBm
0.1
0.2
12 dBm
0.3
3
0.4
2
0.6
1.6
0.8
1.2
1
Figure 22: Output power vs. load impedance at 915 MHz
The schematic of the recommended matching network at the output of the transmitter is shown in Figure 23 below.
The two Π-sections are used to provide harmonic filtering in order to satisfy FCC and ETSI regulations.
CT2
LT1
VDD
XE1203F
CT3
LT2
CT1
CT4
CT5
LT3
Figure 23: Transmitter output network
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XE1203F
The typical component values of this matching circuit are shown below in Table 23:
Name
Typical Value
for 434 MHz
Typical Value
for 868 MHz
Typical Value
for 915 MHz
Tolerance
CT1
6.8 pF
1.5 pF
1.8 pF
± 5%
CT2
1.0 pF
0.56 pF
NC
± 5%
CT3
22 pF
15 pF
33 pF
± 5%
CT4
6.8 pF
3.3 pF
3.3 pF
± 5%
CT5
4.7 pF
2.2 pF
2.2 pF
± 5%
LT1
33 nH
39 nH
47 nH
± 5%
LT2
22 nH
10 nH
10 nH
± 5%
LT3
22 nH
8.2 nH
8.2 nH
± 5%
Table 23: Typical component values for the recommended matching network at the output of the transmitter
6.3
VCO TANK
The tank of the VCO is implemented with one inductor in parallel with one capacitor. The characteristics of these
two components must be as follows:
Name
Typical Value
for 434 MHz
Typical Value
for 868 MHz
Typical Value
for 915 MHz
Tolerance
CV1
1.0 pF
NC
NC
±5%
LV1
33 nH
8.2 nH
6.8 nH
±2%
Table 24: VCO tank external components
6.4
LOOP FILTER OF THE FREQUENCY SYNTHESIZER
The loop filter of the frequency synthesizer is shown in Figure 24 below:
LFB
RL1
CL2
XE1203
XE1203F
CL1
Figure 24: Loop filter of the frequency synthesizer
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XE1203F
The values recommended for applications using bit rates up to 38.4kbit/s are given in Table 25 below:
Name
Typical Value
for 434 MHz
Typical Value
for 868 MHz
Typical Value
for 915 MHz
Tolerance
CL1
22 nF
22 nF
22 nF
± 5%
CL2
1.2 nF
1.2 nF
1.2 nF
± 5%
RL1
560Ω
470Ω
470Ω
± 5%
Table 25: Typical loop filter values for bit rates up to 38.4 kbit/s
The values recommended for applications using bit rates higher than 38.4 kbit/s are given in Table 26 below:
Name
Typical Value
for 434 MHz
Typical Value
for 868 MHz
Typical Value
for 915 MHz
Tolerance
CL1
3.3 nF
4.7nF
4.7 nF
± 5%
CL2
220 pF
330 pF
330 pF
± 5%
RL1
1.2 kΩ
1 kΩ
1 kΩ
± 5%
Table 26: Typical loop filter values for bit rates higher than 38.4 kbit/s
6.5
FREQUENCY SYNTHESIZER REFERENCE CRYSTAL
For narrow band applications, where the lowest frequency deviation and the narrowest baseband filter are selected,
the crystal for reference oscillator of the frequency synthesizer should have the following typical characteristics:
Name
Description
Min. value
Typ. value
Max. value
Fs
Nominal frequency
-
39.0 MHz
(fundamental)
-
CL
Load capacitance for fs (on-chip)
-
8 pF (*)
-
Rm
Motional resistance
-
-
40Ω
Cm
Motional capacitance
-
-
30 fF
C0
Shunt capacitance
-
-
7 pF (*)
∆fs(0)
Calibration tolerance at 25 °C
-
-
10 ppm
∆fs(∆T)
Stability over temperature range
(-40 °C to 85 °C)
-
-
10 ppm
∆fs(∆t)
Aging tolerance in first 5 years
-
-
5 ppm
Table 27: Crystal characteristics
(*) The on-chip oscillator mode is user-defined by programming ADParam_Xsel parameter: the first for CL = 8 pF
and C0 = 7pF, and the second for CL = 8 pF and C0 = 3 pF; the latter will allow higher amplitude for the internal
signal with a slightly lower consumption.
The electrical specifications given in section 3.2.2 are valid for a crystal having the specifications given in Table 27.
For wide band applications requiring less frequency stability, the values for ∆fs(0), ∆fs(∆T), and/or ∆fs(∆t) can be
relaxed. In this case foffset + BWssb should be lower than BWfilter, where foffset is the offset (error) on the carrier
frequency (the sum of ∆fs(0), ∆fs(∆T), and/or ∆fs(∆t)), BWssb is the single side-band bandwidth of the signal, and
BWfilter is the single side-band bandwidth of the base-band filter.
The overtone crystal usage may result in higher oscillator start-up time than fundamental mode. The overtone
crystal should be designed for Cload = 8 to 10 pF and has parameters of Rm < 60Ω, C0 < 7 pF.
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XE1203F
7
PACKAGING INFORMATION
XE1203F is available in a 48-lead VQFN RoHS green package as shown in Figure 25 below.
Please note that the Exposed Die Pad should be connected to ground
Figure 25: Package Dimensions
© Semtech 2007
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Contact Information
Semtech Corporation
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200 Flynn Road, Camarillo, CA 93012
Phone (805) 498-2111 Fax : (805) 498-3804
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