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Product Description
Ordering Information
Typical Applications
Features
Functional Block Diagram
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
Optimum Technology Matching Applied
Si BJT
GaAs MESFET
GaAs HBT
Si Bi-CMOS
SiGe HBT
Si CMOS
InGaP/HBT
GaN HEMT
SiGe Bi-CMOS
17 18
26
12
11
9
Linear
RSSI
24
7
5
Gain
Control
47
3
31 30
34
Prescaler
128/129 or
64/65
Phase
Detector &
Charge Pump
41
40 39 38
35
36
Lock
Detector
42
43
Ref
Select
37
14
13
DATA OUT
RSSI
DIV CTRL
MOD CTRL
OSC SEL
23
MUTE
IF
2
IN
IF
1
OUT
21
IF2 BP+
20
VREF IF
22
IF2 BP-
16
IF1 BP-
15
IF1 BP+
IF
1
IN-
IF
1
IN+
MIX OUT-
MIX OUT+
MIX IN
LNA OUT
RX IN
TX OUT
LVL ADJ
RESNTR+
MOD IN
VREF P
LOCK DET
LOOP FLT
OSC B1
OSC B2
OSC E
45 PRESCL OU
28
IF
2
OUT
27
DEMOD IN
RESNTR-
25 FM OUT
RF2905
433/868/915MHz FM/FSK/ASK/OOK
TRANSCEIVER
Wireless Meter Reading
Keyless Entry Systems
433/868/915MHz ISM Band Systems
Wireless Data Transceiver
Wireless Security Systems
Battery Powered Portable Devices
The RF2905 is a monolithic integrated circuit intended for
use as a low cost FM transceiver. The device is provided
in 7mmx7mm, 48-lead plastic LQFP packaging and is
designed to provide a fully functional FM transceiver. The
chip is intended for linear (AM, FM) or digital (ASK, FSK,
OOK) applications in the North American 915MHz ISM
band and European 433MHz and 868MHz ISM bands.
The integrated VCO, dual modulus/dual divide (128/129
or 64/65) prescaler, and reference oscillator require only
the addition of an external crystal to provide a complete
phase-locked oscillator.
Fully Monolithic Integrated Transceiver
2.7V to 5.0V Supply Voltage
Narrow Band and Wide Band FM/FSK
300MHz to 1000MHz Frequency Range
10dB Cascaded Noise Figure
10mW Output Power at 433MHz
RF2905
433/868/915MHz FM/FSK/ASK/OOK Transceiver
RF2905 PCBA-L Fully Assembled Evaluation Board (433MHz)
RF2905 PCBA-M Fully Assembled Evaluation Board (868MHz)
0
Rev B12 021008
Dimensions in mm.
7.00
+ 0.10 sq.
9.00
+ 0.20 sq.
0.22
+ 0.05
7 MAX
0 MIN
0.60
0.15
0.10
+
0.127
1.40
+ 0.05
0.50
0.35
0.25
Package Style: LQFP-48, 7x7
NOT FOR NEW DESIGNS
!
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Absolute Maximum Ratings
Parameter
Ratings
Unit
Supply Voltage
-0.5 to +5.5
V
DC
Control Voltages
-0.5 to +5.0
V
DC
Input RF Level
+10
dBm
Output Load VSWR
50:1
Operating Ambient Temperature
-40 to +85
C
Storage Temperature
-40 to +150
C
Parameter
Specification
Unit
Condition
Min.
Typ.
Max.
Overall
T=25 C, V
CC
=3.6V, Freq=915MHz
RF Frequency Range
300 to 1000
MHz
VCO and PLL Section
VCO Frequency Range
300 to 1000
MHz
Prescaler divide ratio
64/65 or 128/129
Prescaler Output Impedance
50
PLL Phase Noise
-75
dBc/Hz
Freq=915MHz, 10kHz Offset, 5kHz Loop
Bandwidth
-100
dBc/Hz
Freq=915MHz, 100kHz Offset, 5kHz loop
Bandwidth
Reference Frequency
TBD
17
MHz
Crystal R
S
50
100
Charge Pump Current
-40
+40
A
Transmit Section
Max Modulation Frequency
2
MHz
Min Modulation Frequency
Set by loop filter bandwidth
Maximum Power Level
+7
+10
dBm
Freq=433MHz
0
+3
8
dBm
Freq=915MHz
Power Control Range
12
dB
Power Control Sensitivity
10
dB/V
Max FM Deviation
200
kHz
Instantaneous frequency deviation is
inversely proportional with the modulation
voltage
Antenna Port Impedance
50
TX ENABL="1". RX ENABL="0"
Antenna Port VSWR
1.5:1
TX Mode
Modulation Input Impedance
4
k
Harmonics
-23
dBc
Spurious
dBc
Compliant to Part 15.249 and I-ETS 300 220
Overall Receive Section
Frequency Range
300 to 1000
MHz
Cascaded Voltage Gain
35
dB
Freq=433MHz
23
dB
Freq=915MHz
Cascaded Noise Figure
10
dB
Cascaded Input IP
3
-31
dBm
Freq=433MHz
-26
dBm
Freq=915MHz
RX Sensitivity
-95
-101
dBm
IF BW=180kHz, Freq=915MHz, S/N=8dB
LO Leakage
-70
dBm
RSSI DC Output Range
0.5 to 2.5
V
R
LOAD
=51k
RSSI Sensitivity
25
mV/dB
RSSI Dynamic Range
70
80
dB
Caution! ESD sensitive device.
RF Micro Devices believes the furnished information is correct and accurate
at the time of this printing. However, RF Micro Devices reserves the right to
make changes to its products without notice. RF Micro Devices does not
assume responsibility for the use of the described product(s).
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Parameter
Specification
Unit
Condition
Min.
Typ.
Max.
LNA
Voltage Gain
23
dB
433MHz
16
dB
915MHz
Noise Figure
4.8
dB
433MHz
5.5
dB
915MHz
Input IP
3
-27
dBm
433MHz
-20
dBm
915MHz
Input P
1dB
-37
dBm
433MHz
-30
dBm
915MHz
Antenna Port Impedance
50
RX ENABL="1". TX ENABL="0"
Antenna Port VSWR
1.5:1
RX Mode
Output Impedance
Open Collector
433MHz
Open Collector
915MHz
Mixer
Single-ended configuration
Conversion Voltage Gain
8
dB
433MHz
7
dB
915MHz
Noise Figure (SSB)
10
dB
433MHz
17
dB
915MHz
Input IP
3
-21
dBm
433MHz
-17
dBm
915MHz
Input P
1dB
-31
dBm
433MHz
-28
dBm
915MHz
Maximum Output Voltage
V
PP
Balanced
First IF Section
IF Frequency Range
0.1
10.7
25
MHz
Voltage Gain
34
dB
IF=10.7MHz, Z
L
=330
Noise Figure
13
dB
IF1 Input Impedance
330
IF1 Output Impedance
330
Second IF Section
IF Frequency Range
0.1
10.7
25
MHz
Voltage Gain
60
dB
IF=10.7MHz
IF2 Input Impedance
330
IF2 Output Impedance
1
k
At IF2 OUT- pin
Demod Input Impedance
10
k
FM Output Impedance
500
Data Output Impedance
>1
FM Output Bandwidth
500
kHz
3dB Bandwidth, Dependent upon IF band-
width and Discriminator.
Data Output Bandwidth
500
kHz
3dB Bandwidth, Z
LOAD
=1M
|| 3pF; Depen-
dent upon IF bandwidth and Discriminator.
Data Output Level
0.3
V
CC
-0.3
V
Z
LOAD
=1M
|| 3pF; Output voltage is pro-
portional with the instantaneous frequency
deviation.
FM Output DC Level
2.6
V
Z
LOAD
>10k
FM Output AC Level
200
mV
PP
Z
LOAD
>10k
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Parameter
Specification
Unit
Condition
Min.
Typ.
Max.
Power Down Control
Logical Controls "ON"
2.0
V
Voltage supplied to the input
Logical Controls "OFF"
1.0
V
Voltage supplied to the input
Control Input Impedance
25k
Turn On Time
4
ms
Reference Crystal=7.075MHz
Turn Off Time
4
ms
Dependent upon reference crystal. Higher
RX to TX and TX to RX Time
4
ms
frequencies reduce turn on/off times
Power Supply
Voltage
3.6
V
Specifications
2.7 to 5.0
V
Operating limits
Current Consumption
22
25
34.5
mA
TX Mode, LVL ADJ=3.6V
8
10
13.5
mA
TX Mode, LVL ADJ=0V
7
9
12
mA
RX Mode
1
A
Power Down Mode which sets:
PLL ENABL, TX ENABL, RX ENABL,
LVL ADJ, OSC SEL, and MUTE=0V
5.3
8
10
mA
PLL Only Mode
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Pin
Function
Description
Interface Schematic
1
RX ENABL
Enable pin for the receiver circuits. RX ENABL>2.0V powers up all
receiver functions. RX ENABL<1.0V turns off all receiver functions
except the PLL functions and the RF mixer.
2
TX ENABL
Enables the transmitter circuits. TX ENABL>2.0V powers up all trans-
mitter functions. TX ENABL<1.0V turns off all transmitter functions
except the PLL functions.
3
TX OUT
RF output pin for the transmitter electronics. TX OUT output impedance
is a low impedance when the transmitter is enabled. TX OUT is a high
impedance when the transmitter is disabled.
4
GND2
Ground connection for the 40dB IF limiting amplifier and Tx PA func-
tions. Keep traces physically short and connect immediately to ground
plane for best performance.
5
RX IN
RF input pin for the receiver electronics. RX IN input impedance is a
low impedance when the transmitter is enabled. RX IN is a high imped-
ance when the receiver is disabled.
6
GND1
Ground connection for RF receiver functions. For best performance,
keep traces physically short and connect immediately to ground plane.
7
LNA OUT
Output pin for the receiver RF low noise amplifier. This pin is an open
collector output and requires an external pull up coil to provide bias and
tune the LNA output.
8
GND3
Same as pin 4.
9
MIX IN
RF input to the RF Mixer. An LC matching network between LNA OUT
and MIX IN can be used to connect the LNA output to the RF mixer
input in applications where an image filter is not needed or desired.
10
GND5
GND5 is the ground connection shared by the input stage of the trans-
mit power amplifier and the receiver RF mixer.
11
MIX OUT+
Complementary (with respect to pin 12) IF output from the RF mixer.
Interfaces directly to 10.7MHz ceramic IF filters as shown in the appli-
cation schematic. A pull-up inductor and series matching capacitor
should be used to present a 330
termination impedance to the
ceramic filter. Alternately, an IF tank can be used to tailor the IF fre-
quency and bandwidth to meet the needs of a given application.
12
MIX OUT-
IF output from the RF mixer. For a balanced mixer output, pull-up induc-
tors from pin 11 and 12 to V
CC
and a capacitor between the pins should
be used. The sum of the total pull-up inductance should be used to res-
onate the capacitor between pins 11 and 12. DC blocking capacitors of
10nF can then be used to connect the balanced output to IF1 IN+ (pin
13) and IF1 IN- (pin 14).
See pin 11.
50 k
RX ENABL
40 k
20 k
TX ENABL
TX OUT
20
V
CC
RX IN
500
LNA OUT
V
CC
GND5
MIX IN
MIX OUT
MIX OUT+
15 pF
15 pF
GND5
GND5
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