SiW1721B
0
Features
• Integrated RF transceiver and
modem for Bluetooth wireless
technology.
• Manufactured using low-power
0.18-micron CMOS process
technology.
• Digital baseband interface connects
directly to an integrated Bluetooth
controller.
• Direct conversion RF architecture
improves receiver-blocking
performance.
• Low out-of-band spurious emissions
minimize interference with mobile
phone operations.
• Hardware AGC dynamically adjusts
receiver performance in changing
environments.
• 50
Ω
RF I/O does not need additional
external impedance matching
components.
• On-chip voltage regulation simplifies
system design.
• -88 dBm receiver sensitivity and
+2 dBm transmitter power typical
performance specifications.
• Bluetooth Specification V2.0
qualified. Complies with Bluetooth
specifications V1.1, V1.2 and V2.0.
Reference
Clock
Ext
Power
SiW1721B Radio Modem
Single-ended LNA
ADC
and Downconverter
Single-ended Driver
DAC
and Upconverter
GFSK
Demodulator
GFSK
Modulator
Radio
Programming
and Control
SPI
CLK Circuit
Analog
Regulator
Digital
Regulator
Mobile Phone
Chip Set
BLUETOOTH® RADIO MODEM
Modem I/F
& Data
Reference
PLL
Modem
Clock
Generator
Integrated
Bluetooth
Baseband
Bluetooth Subsystem Using the SiW1721B Radio Modem
Summary
The SiW1721B is a 2.4-GHz radio transceiver for Bluetooth wireless
technology. This highly integrated transceiver is specifically designed for use
with a third party Bluetooth baseband controller chipset requiring an
external Bluetooth RF transceiver. Due to its low power CMOS process, the
design minimizes current draw in both active and standby modes.
The SiW1721B combines a radio transceiver and Gaussian Frequency Shift
Keying (GFSK) modem with digital control and interface logic. The IC also
incorporates analog and digital voltage regulators and a reference Phase
Lock Loop (PLL) capable of accepting various reference clock frequencies.
The level of integration enables a low system cost with fewer external
components.
The SiW1721B is packaged in a 5-by-5-mm, Pb-free, 32-pin QFN package
that meets RoHS (Green) requirements. Operating temperature range is
guaranteed from -40°C to +85°C.
Applications
• Mobile phones with integrated
controller for Bluetooth wireless
technology.
Ordering Information
SiW1721B
Bluetooth® Radio Modem
See page 12 for details.
Optimum Technology Matching® Applied
Si BJT
Si Bi-CMOS
GaInP/HBT
GaAs HBT
SiGe HBT
GaN HEMT
GaAs MESFET
Si CMOS
SiGe Bi-CMOS
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
60 0076 R00F SiW1721B Radio Modem IC DS
October 6, 2006
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SiW1721B
Description
The following figure shows the SiW1721B Radio Modem functional block diagram. During the receive process, the radio
signal is taken from the single-ended RF input pin that feeds into the low noise amplifier (LNA). The signal from the LNA is
directly down-converted to I/Q baseband, filtered with an anti-aliasing filter, and converted to a digital signal with a high
resolution analog-to-digital converter. The critical channel filtering is done in the digital domain for stable and repeatable
performance. The signal is then processed by a high performance GFSK demodulator. The IC has multiple internal self-
calibration circuits to maintain stable and repeatable performance from part-to-part as well as over the full temperature
range.
The IC has two fully integrated regulators: one for the radio (analog regulator) and one for the digital logic (digital
regulator). The digital regulator can be used to supply a Bluetooth baseband controller. Both regulators can be bypassed if
external regulation is desired.
Note:
When bypassing the analog regulator, the VBATT_ANA and VCC_OUT pins must be tied together and the external analog
voltage (1.8 V) should be applied to the VBATT_ANA pin. When bypassing the digital regulator, the VBATT_DIG pin should be
left unconnected and the external digital voltage (1.8 V) should be applied to the VBB_OUT pin.
The IC also provides power on reset and glitch-free clock start-up. A reference PLL can be enabled to support a number of
different reference frequencies.
Digital control functions and a programming interface provide radio modem control and a flexible interface to external
Bluetooth link controllers.
XTAL_P/CLK
VBATT_ANA
CHG_PUMP
VBATT_DIG
VCC_OUT
VBB_OUT
RESET_N
BB_CLK
VTUNE
PLL
Control
Clock Distribution
LNA
Voltage Regulators and
Power Distribution
ADC
0
90
Internal
50-Ohm
Match
Network
ADC
PLL
Synthesizer
Power
Control
0
90
DAC
GFSK
Modem
RF_IO
IDAC
VDD_IO
RX_TX_DATA
CD_TXEN
ENABLE_RM
HOP_STROBE
TX_RX_SWITCH
TX_BIAS
SPI_SS
SPI_TXD
SPI_RXD
SPI_CLK
Serial
Programming
Interface
(SPI)
DAC
Register
File
System
Control
SiW1721B Block Diagram
Radio Interface
An internal power control loop maintains a very stable RF_IO signal level over the full temperature range and from part to
part. This means predictable and repeatable range at any temperature.
Modem Interface
The modem interface transfers the Bluetooth data between the SiW1721B Radio Modem and the ASIC. For reference
purposes, the pin description table (Table 1) provides a brief description of typical interface modes.
Clock Signals
Multiple reference clock frequencies can be used as a reference for the RF circuits, to synthesize clocks for most of the
internal digital circuits, and to supply external processors with timing signals.
Serial Programming Interface (SPI)
The serial programming interface (SPI) is used to access the internal registers of the SiW1721B Radio Modem. The SPI is
a synchronous serial interface that can be clocked to a nominal speed of 8MHz.
Power
The SiW1721B Radio Modem includes both analog and digital voltage regulators. Input options are based on factors such
as voltage source, where internal regulators are used, and I/O voltage.
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60 0076 R00F SiW1721B Radio Modem IC DS
VCC
SiW1721B
Pin Description
The SiW1721B Radio Modem’s radio and modem interface (SPI), a single clock input, and supply voltage are required for
proper operation.
Name
RF_IO
IDAC
Pad Type
Analog
Analog
Description
Combined 50
Ω
input and output pin in normal mode. Rx only in power class 1 mode.
Power control to external power amplifier. This output provides a variable current source that
can be used to control the external power amp. Leave unconnected if not used.
Output signal to indicate the current state of the radio. The polarity is programmable with the
default set as:
Low=Transmit mode.
High=Non-transmit mode.
Bias for the output driver in normal mode, transmit output in power class 1 mode.
Radio Interface Signal Description
TX_RX_SWITCH
TX_BIAS
CMOS output
Analog
CMOS
bi-directional
CMOS
bi-directional
Modem Interface Description
RX_TX_DATA
Received sliced-mode data from radio; or transmit data to radio.
Dual function carrier detect and transmit enable. This bi-directional signal can be enabled
through internal registers. During transmit, this pin can be used as an INPUT to indicate valid
transmit data (TXEN). During receive, this pin can be used as an OUTPUT to indicate carrier
detect (CD). Input only, output, or bi-directional.
Sleep/wake control signal from baseband controller. Used to command the SiW1721B Radio
Modem from idle to sleep mode, and to awaken the SiW1721B Radio Modem from sleep
mode.
Signal generated by the baseband to indicate the start of TX or RX ramp-up.
Reset for digital circuits only. State machines and internal registers reset to their default state.
This signal is an asynchronous input with a minimum pulse width requirement of 10 µs.
System clock crystal positive input or reference clock input. For additional information see the
“Crystal Requirements” and “External Reference Requirements” sections.
System clock crystal negative input. If a reference clock frequency is used, this pin should be
left unconnected.
Selectable clock output to external baseband controller. Five frequencies are supported (in
MHz): reference frequency, reference frequency/2, 12, 13, 16, 32, 48, and 52.
BB_CLK stops oscillating when ENABLE_RM is de-asserted (low).
SPI data output from SiW1721B.
SPI data input to SiW1721B.
Clock input used for synchronous data transfer on the SPI bus.
SPI slave select that enables the SiW1721B Radio Modem as the target.
Supply voltage to internal analog voltage regulator.
Supply voltage to internal digital voltage regulator.
Regulated output from internal analog regulator.
Regulated output from internal digital regulator.
Supply voltage to on-chip analog circuits.
Supply voltage to on-chip I/O interface.
I/O pins: BB_CLK, CD_TXEN, ENABLE_RM, HOP_STROBE, RESET_N, RX_TX_DATA,
SPI_CLK, SPI_RXD, SPI_SS, SPI_TXD, TX_RX_SWITCH.
This signal is used to indicate that the internal digital regulator is stable (VBB_OUT).
Decoupling capacitor for voltage reference for the internal A/D converter.
Decoupling capacitor for voltage reference for the internal A/D converter.
Pin for reference PLL loop filter.
Pin for RF PLL loop filter.
CD_TXEN
ENABLE_RM
HOP_STROBE
RESET_N
CMOS input
CMOS input
CMOS input
Clock Signals Description
XTAL_P/CLK
XTAL_N
BB_CLK
Analog
Analog
CMOS output
Serial Programming Interface Description
SPI_TXD
SPI_RXD
SPI_CLK
SPI_SS
VBATT_ANA
VBATT_DIG
VCC_OUT
VBB_OUT
VCC
VDD_IO
VBB_RDY
VREFP_CAP
VREFN_CAP
VTUNE
CHG_PUMP
CMOS output
CMOS input
CMOS input
CMOS input
Power
Power
Power
Power
Power
Power
CMOS output
Analog
Analog
Analog
Analog
Power Signals Description
Other I/O Description
Table 1. SiW1721B Radio Modem Pin List
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SiW1721B
System Specifications
Absolute Maximum Ratings
Parameter
V
CC
V
DD_IO
V
BATT_ANA
V
BATT_DIG
T
ST
RF
MAX
Analog circuit supply voltage
I/O supply voltage
Analog regulator supply voltage
Digital regulator supply voltage
Storage temperature
Maximum RF input level
Description
Min
-0.3
-0.3
-0.3
-0.3
-55
–
Max
3.63
3.63
3.63
3.63
+125
+5
Unit
V
V
V
V
°C
dBm
Note: Absolute maximum ratings indicate limits beyond which the useful life of the device may be impaired or damage may occur.
Recommended Operating Conditions
Parameter
T
OP
V
BATT_ANA
V
BATT_DIG
V
CC
V
DD_IO
Description
Operating temperature (industrial grade)
Supply for internal analog voltage regulator
Supply for internal digital voltage regulator
Analog supply voltage
Digital interface I/O supply voltage
Min
-40
2.3
2.3
1.71
1.62
Max
+85
3.63
3.63
1.89
3.63
Unit
°C
V
V
V
V
ESD Rating
Symbol
ESD
1
Description
ESD protection - all pins
1
Rating
2000 V
This device is a high performance RF integrated circuit with an ESD rating of 2,000 volts (HBM conditions per Mil-Std-883, Method 3015). Handling and
assembly of this device should only be done using appropriate ESD controlled processes.
Electrical Characteristics
DC Specification
(T
OP
=+25°C, V
DD_IO
=3.0V)
Symbol
V
IL
V
IH
V
OL
V
OH
I
OH
I
OL
I
ILI
Input low voltage
Input high voltage
Output low voltage
Output high voltage
Output high current
Output high current (pins 16, 19)
Output low current
Output low current (pins 16, 19)
Input leakage current
Description
Min.
GND-0.1
0.7*V
DD_IO
GND
0.8*V
DD_IO
–
–
–
–
–
Typ.
–
–
–
–
500
4
500
4
<1
Max.
0.3*V
DD_IO
V
DD_IO
0.2*V
DD_IO
V
DD_IO
–
–
–
–
1
Unit
V
V
V
V
µA
mA
µA
mA
µA
AC Characteristics (T
OP
=+25°C, V
DD_IO
=3.0V, C
LOAD
=15pF)
Symbol
Description
Min.
t
r
t
f
Rise time
Rise time (pins 16, 19)
Fall time
Fall time (pins 16, 19)
–
–
–
–
Typ.
–
–
–
–
Max.
30
16
24
13
Unit
ns
ns
ns
ns
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60 0076 R00F SiW1721B Radio Modem IC DS
SiW1721B
Current Consumption
(T
OP
=+25°C, V
BATT_ANA
, V
BATT_DIG
= 3.3 V)
Symbol
I
DD_SLEEP
I
DD_IDLE
I
DD_TRANSMIT
I
DD_RECEIVE
Description
Current during sleep mode
Current during idle, synthesizer not running
Current during continuous transmit
Current during continuous receive
Min.
–
–
–
–
Typ.
15
2
41
41
Max.
25
–
45
45
Unit
µA
mA
mA
mA
Radio Specification
Parameter
VCO operating
range
PLL lock time
Frequency
–
Description
Min
2402
–
Typ
–
55
Max
2480
100
Unit
MHz
µs
Receiver Specification
1
(V
BATT_ANA
, V
BATT_DIG
=3.3V, V
CC
=int. analog reg. output, and nominal
2
Bluetooth test conditions)
Parameter
Receiver
sensitivity
Maximum usable
signal
C/I co-channel
(0.1% BER)
C/I 1MHz
(0.1% BER)
C/I 2MHz
(0.1% BER)
C/I
≥3MHz
(0.1% BER)
Out-of-band
blocking
3
Intermodulation
Receiver spurious
emission
1
2
3
Description
Measured based on
BER<0.1%
Measured based on
BER<0.1%
Min
–
-10
–
–
–
–
-10
-27
-27
-10
-39
–
–
Typ
-88
+5
8.0
-4.0
-38.0
-43
–
–
–
–
-36
–
–
Max
-82
–
11.0
0
-35.0
-40
–
–
–
–
–
-57
-47
Unit
dBm
dBm
dB
dB
dB
dB
dBm
dBm
dBm
dBm
dBm
dBm
dBm
Co-channel selectivity
Adjacent channel selectivity
2nd adjacent channel selectivity
3rd adjacent channel selectivity
30 MHz to 2000 MHz
2000 MHz to 2399 MHz
2498 MHz to 3000 MHz
3000 MHz to 12.75 GHz
Max interferer level to maintain 0.1% BER,
interference signals at 3 MHz and 6 MHz offset.
30MHz to 1GHz
1 GHz to 12.75 GHz
Measured into the chip with a
50
Ω
source and no band pass filter.
Nominal and extreme Bluetooth test conditions as defined by the Bluetooth Test Specification.
Out-of-band blocking guaranteed by design.
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