RF Monolithics, Inc.
Phone: (972) 233-2903
Fax: (972) 387-8148
E-mail: info@rfm.com
Page 1 of 10
RFM Europe
Phone: 44 1963 251383
Fax: 44 1963 251510
http://www.rfm.com
1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
RX5001-062805
Designed for Short-Range Wireless Control and Data Communications
Supports RF Data Transmission Rates Up to 115.2 kbps
3 V, Low Current Operation plus Sleep Mode
Stable, Easy to Use, Low External Parts Count
Complies with Directive 2002/95/EC (RoHS)
The RX5001 hybrid receiver is ideal for short-range wireless control and data applications where robust op-
eration, small size, low power consumption and low cost are required. The RX5001 employs RFM's amplifier-
sequenced hybrid (ASH) architecture to achieve this unique blend of characteristics. All critical RF functions
are contained in the hybrid, simplifying and speeding design-in. The RX5001 is sensitive and stable. A wide
dynamic range log detector, in combination with digital AGC and a compound data slicer, provide robust per-
formance in the presence of on-channel interference or noise. Two stages of SAW filtering provide excellent
receiver out- of-band rejection. The RX5001 generates virtually no RF emissions, facilitating compliance with
FCC Part 15 and similar regulations.
Rating
Value
Units
Power Supply and All Input/Output Pins
-0.3 to +4.0
V
Non-Operating Case Temperature
-50 to +100
C
Soldering Temperature (10 seconds / 5 cycles max.)
260
C
315.00 MHz
Hybrid
Receiver
RX5001
SM-20L Case
Electrical Characteristics
Characteristic
Sym
Notes
Minimum
Typical
Maximum
Units
Operating Frequency
f
o
314.80
315.20
MHz
Modulation Types
OOK & ASK
Data Rate
115.2
kbps
Receiver Performance, High Sensitivity Mode
Sensitivity, 2.4 kbps, 10-3 BER, AM Test Method
1
-109
dBm
Sensitivity, 2.4 kbps, 10-3 BER, Pulse Test Method
1
-103
dBm
Current, 2.4 kbps (R
PR
= 330 K)
2
3.0
mA
Sensitivity, 19.2 kbps, 10-3 BER, AM Test Method
1
-105
dBm
Sensitivity, 19.2 kbps, 10-3 BER, Pulse Test Method
1
-99
dBm
Current, 19.2 kbps (R
PR
= 330 K)
2
3.1
mA
Sensitivity, 115.2 kbps, 10-3 BER, AM Test Method
1
-101
dBm
Sensitivity, 115.2 kbps, 10-3 BER, Pulse Test Method
1
-95
dBm
Current, 115.2 kbps
3.8
mA
Receiver Performance, Low Current Mode
Sensitivity, 2.4 kbps, 10-3 BER, AM Test Method
1
-104
dBm
Sensitivity, 2.4 kbps, 10-3 BER, Pulse Test Method
1
-98
dBm
Current, 2.4 kbps (R
PR
= 1100 K)
2
1.8
mA
RF Monolithics, Inc.
Phone: (972) 233-2903
Fax: (972) 387-8148
E-mail: info@rfm.com Page 2 of 10
RFM Europe
Phone: 44 1963 251383
Fax: 44 1963 251510
http://www.rfm.com
1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
RX5001-062805
Electrical Characteristics (typical values given for 3.0 Vdc power supply, 25 C)
Characteristic
Sym
Notes
Minimum
Typical
Maximum
Units
Receiver Out-of-Band Rejection, 5% fo
R
5%
3
80
dB
Receiver Ultimate Rejection
R
ULT
3
100
dB
Sleep Mode Current
I
S
0.7
A
Power Supply Voltage Range
V
CC
2.2
3.7
Vdc
Power Supply Voltage Ripple
10
mV
P-P
Ambient Operating Temperature
T
A
-40
85
C
Notes:
1. Typical sensitivity data is based on a 10
-3
bit error rate (BER), using DC-balanced data. There are two test methods commonly used to measure
OOK/ASK receiver sensitivity, the "100% AM" test method and the "Pulse" test method. Sensitivity data is given for both test methods. See Ap-
pendix 3.8 in the
ASH Transceiver Designer's Guide for the details of each test method, and for sensitivity curves for a 2.2 to 3.7 V supply voltage
range at five operating temperatures. The application/test circuit and component values are shown on the next page and in the
Designer's Guide.
2. At low data rates it is possible to adjust the ASH pulse generator to trade-off some receiver sensitivity for lower operating current. Sensitivity
data and receiver current are given at 2.4 kbps for both high sensitivity operation (R
PR
= 330 K) and low current operation (R
PR
= 1100 K).
3. Data is given with the ASH radio matched to a 50 ohm load. Matching component values are given on the next page.
4. See Table 1 on Page 8 for additional information on ASH radio event timing.
Dimension
mm
Inches
Min
Nom
Max
Min
Nom
Max
A
10.795
10.922
11.049
.425
.430
.435
B
9.525
9.652
9.779
.375
.380
.385
C
1.778
1.905
2.032
.070
.075
.080
D
3.048
3.175
3.302
.120
.125
.130
E
0.381
0.508
0.635
.015
.020
.025
F
0.889
1.016
1.143
.035
.040
.045
G
3.175
3.302
3.429
.125
.130
.135
H
1.778
1.905
2.032
.070
.075
0.80
3
4
5
6
7
9
11
12
13
14
15
16
17
19
ASH Transceiver Pin Out
RFIO
8
2
10
20
1
18
LPFADJ
RREF
THLD2
AGCCAP
PKDET
BBOUT
CMPIN
RXDATA
TXMOD
THLD1
PRATE
PWIDTH
GND1
VCC1
GND2
VCC2
GND3
CNTRL0
CNTRL1
SM-20L Package Drawing
C
D
E
F
G
A
B
H
RF Monolithics, Inc.
Phone: (972) 233-2903
Fax: (972) 387-8148
E-mail: info@rfm.com Page 3 of 10
RFM Europe
Phone: 44 1963 251383
Fax: 44 1963 251510
http://www.rfm.com
1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
RX5001-062805
Data Output
TOP VIEW
GND
3
CNT
RL0
CNT
RL1
P
WIDTH
P
RATE
THLD
1
NC
RREF
GND2
NC
RX
DATA
LPF
ADJ
CMP
IN
BB
OUT
PK
DET
RF
A1
VCC
1
VCC
2
RFIO
GND1
+ 3
VDC
ASH Receiver Application Circuit
OOK Configuration
1
20
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
+ 3
VDC
R
PW
R
PR
R
TH1
R
REF
R
LPF
C
BBO
C
DCB
L
AT
L
ESD
C
RFB1
+
R/S
C
LPF
R
BBO
Data Output
TOP VIEW
GND
3
CNT
RL0
CNT
RL1
P
WIDTH
P
RATE
THLD
1
THLD
2
RREF
GND2
NC
RX
DATA
LPF
ADJ
CMP
IN
BB
OUT
PK
DET
AGC
CAP
VCC
1
VCC
2
RFIO
GND1
+ 3
VDC
ASH Receiver Application Circuit
ASK Configuration
1
20
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
+ 3
VDC
R
PW
R
PR
R
TH1
R
TH2
R
REF
R
LPF
C
BBO
C
PKD
C
AGC
C
DCB
L
AT
L
ESD
C
RFB1
+
R/S
Item
Symbol
OOK
OOK
ASK
Units
Notes
Nominal NRZ Data Rate
DR
NOM
2.4
19.2
115.2
kbps
see page 1& 2
Minimum Signal Pulse
SP
MIN
416.67
52.08
8.68
s
single bit
Maximum Signal Pulse
SP
MAX
1666.68
208.32
34.72
s
4 bits of same value
AGCCAP Capacitor
C
AGC
-
-
2200
pF
10% ceramic
PKDET Capacitor
C
PKD
-
-
0.001
F
10% ceramic
BBOUT Capacitor
C
BBO
0.1
0.015
0.0027
F
10% ceramic
BBOUT Resistor
R
BBO
12
0
0
K
5%
LPFAUX Capacitor
C
LPF
0.0047
-
-
F
5%
LPFADJ Resistor
R
LPF
300
100
15
K
5%
RREF Resistor
R
REF
100
100
100
K
1%
THLD2 Resistor
R
TH2
-
-
100
K
1%, for 6 dB below peak
THLD1 Resistor
R
TH1
0
0
10
K
1%, typical values
PRATE Resistor
R
PR
330
330
160
K
5%
PWIDTH Resistor
R
PW
270 to GND
270 to GND
1000 to Vcc
K
5%
DC Bypass Capacitor
C
DCB
4.7
4.7
4.7
F
tantalum
RF Bypass Capacitor 1
C
RFB1
100
100
100
pF
5% NPO
Antenna Tuning Inductor
L
AT
82
82
82
nH
50 ohm antenna
Shunt Tuning/ESD Inductor
L
ESD
33
33
33
nH
50 ohm antenna
Receiver Set-Up, 3.0 Vdc, -40 to +85 C
CAUTION: Electrostatic Device. Observe precautions when handling.
RF Monolithics, Inc.
Phone: (972) 233-2903
Fax: (972) 387-8148
E-mail: info@rfm.com Page 4 of 10
RFM Europe
Phone: 44 1963 251383
Fax: 44 1963 251510
http://www.rfm.com
1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
RX5001-062805
ASH Receiver Block Diagram & Timing Cycle
Antenna
Pulse
Generator
SAW
Delay Line
SAW Filter
RFA1
RFA2
Data
Out
Detector &
Low-Pass
Filter
RF Data Pulse
P1
P2
RFA1 Out
RF Input
P1
Delay Line
Out
P2
t
PW2
t
PW1
t
PRI
t
PRC
Figure 1
ASH Receiver Theory of Operation
Introduction
RFM's RX5000 series amplifier-sequenced hybrid (ASH) receivers are
specifically designed for short-range wireless control and data communica-
tion applications. The receivers provide robust operation, very small size,
low power consumption and low implementation cost. All critical RF func-
tions are contained in the hybrid, simplifying and speeding design-in. The
ASH receiver can be readily configured to support a wide range of data
rates and protocol requirements. The receiver features virtually no RF
emissions, making it easy to certify to short-range (unlicensed) radio regu-
lations.
Amplifier-Sequenced Receiver Operation
The ASH receiver's unique feature set is made possible by its system ar-
chitecture. The heart of the receiver is the amplifier- sequenced receiver
section, which provides more than 100 dB of stable RF and detector gain
without any special shielding or decoupling provisions. Stability is achieved
by distributing the total RF gain over
time. This is in contrast to a superhet-
erodyne receiver, which achieves stability by distributing total RF gain over
multiple frequencies.
Figure 1 shows the basic block diagram and timing cycle for an amplifier-
sequenced receiver. Note that the bias to RF amplifiers RFA1 and RFA2
are independently controlled by a pulse generator, and that the two ampli-
fiers are coupled by a surface acoustic wave (SAW) delay line, which has
a typical delay of 0.5 s.
An incoming RF signal is first filtered by a narrow-band SAW filter, and is
then applied to RFA1. The pulse generator turns RFA1 ON for 0.5 s. The
amplified signal from RFA1 emerges from the SAW delay line at the input
to RFA2. RFA1 is now switched OFF and RFA2 is switched ON for 0.55 s,
amplifying the RF signal further. The ON time for RFA2 is usually set at 1.1
times the ON time for RFA1, as the filtering effect of the SAW delay line
stretches the signal pulse from RFA1 somewhat. As shown in the timing di-
agram, RFA1 and RFA2 are never on at the same time, assuring excellent
receiver stability. Note that the narrow-band SAW filter eliminates sampling
sideband responses outside of the receiver passband, and the SAW filter
and delay line act together to provide very high receiver ultimate rejection.
Amplifier-sequenced receiver operation has several interesting character-
istics that can be exploited in system design. The RF amplifiers in an am-
plifier-sequenced receiver can be turned on and off almost instantly,
allowing for very quick power-down (sleep) and wake-up times. Also, both
RF amplifiers can be off between ON sequences to trade-off receiver noise
figure for lower average current consumption. The effect on noise figure
can be modeled as if RFA1 is on continuously, with an attenuator placed in
front of it with a loss equivalent to 10*log
10
(RFA1 duty factor), where the
duty factor is the average amount of time RFA1 is ON (up to 50%). Since
an amplifier-sequenced receiver is inherently a sampling receiver, the
overall cycle time between the start of one RFA1 ON sequence and the
start of the next RFA1 ON sequence should be set to sample the narrowest
RF data pulse at least 10 times. Otherwise, significant edge jitter will be
added to the detected data pulse.
RF Monolithics, Inc.
Phone: (972) 233-2903
Fax: (972) 387-8148
E-mail: info@rfm.com Page 5 of 10
RFM Europe
Phone: 44 1963 251383
Fax: 44 1963 251510
http://www.rfm.com
1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
RX5001-062805
Figure 2
RX5000 Series ASH Receiver Block Diagram
Figure 2 is the general block diagram of the RX5000 series ASH receiver.
Please refer to Figure 2 for the following discussions.
Antenna Port
The only external RF components needed for the receiver are the antenna
and its matching components. Antennas presenting an impedance in the
range of 35 to 72 ohms resistive can be satisfactorily matched to the RFIO
pin with a series matching coil and a shunt matching/ESD protection coil.
Other antenna impedances can be matched using two or three compo-
nents. For some impedances, two inductors and a capacitor will be re-
quired. A DC path from RFIO to ground is required for ESD protection.
Receiver Chain
The output of the SAW filter drives amplifier RFA1. This amplifier includes
provisions for detecting the onset of saturation (AGC Set), and for switching
between 35 dB of gain and 5 dB of gain (Gain Select). AGC Set is an input
to the AGC Control function, and Gain Select is the AGC Control function
output. ON/OFF control to RFA1 (and RFA2) is generated by the Pulse
Generator & RF Amp Bias function. The output of RFA1 drives the SAW
delay line, which has a nominal delay of 0.5 s.
The second amplifier, RFA2, provides 51 dB of gain below saturation. The
output of RFA2 drives a full-wave detector with 19 dB of threshold gain. The
onset of saturation in each section of RFA2 is detected and summed to pro-
vide a logarithmic response. This is added to the output of the full-wave de-
tector to produce an overall detector response that is square law for low
signal levels, and transitions into a log response for high signal levels. This
combination provides excellent threshold sensitivity and more than 70 dB
of detector dynamic range. In combination with the 30 dB of AGC range in
RFA1, more than 100 dB of receiver dynamic range is achieved.
The detector output drives a gyrator filter. The filter provides a three-pole,
0.05 degree equiripple low-pass response with excellent group delay flat-
ness and minimal pulse ringing. The 3 dB bandwidth of the filter can be set
from 4.5 kHz to 1.8 MHz with an external resistor.
The filter is followed by a base-band amplifier which boosts the detected
signal to the BBOUT pin. When the receiver RF amplifiers are operating at
a 50%-50% duty cycle, the BBOUT signal changes about 10 mV/dB, with
a peak-to-peak signal level of up to 685 mV. For lower duty cycles, the mV/
dB slope and peak-to-peak signal level are proportionately less. The de-
tected signal is riding on a 1.1 Vdc level that varies somewhat with supply
voltage, temperature, etc. BBOUT is coupled to the CMPIN pin or to an ex-
ternal data recovery process (DSP, etc.) by a series capacitor. The correct
value of the series capacitor depends on data rate, data run length, and
other factors as discussed in the
ASH Transceiver Designer's Guide.
When an external data recovery process is used with AGC, BBOUT must
be coupled to the external data recovery process and CMPIN by separate
series coupling capacitors. The AGC reset function is driven by the signal
applied to CMPIN.
When the receiver is placed in the power-down (sleep) mode, the output
impedance of BBOUT becomes very high. This feature helps preserve the
charge on the coupling capacitor to minimize data slicer stabilization time
when the receiver switches out of the sleep mode.
Data Slicers
The CMPIN pin drives two data slicers, which convert the analog signal
from BBOUT back into a digital stream. The best data slicer choice de-
pends on the system operating parameters. Data slicer DS1 is a capacitive-
ly-coupled comparator with provisions for an adjustable threshold. DS1
provides the best performance at low signal-to-noise conditions. The
RX5000 Series ASH Receiver Block Diagram
RFA1
RFA2
SAW
Delay Line
SAW
CR Filter
Log
Antenna
RFIO
ESD
Choke
Detector
Low-Pass
Filter
BB
AGC
Control
Peak
Detector
Pulse Generator
& RF Amp Bias
LPFADJ
PRATE
PWIDTH
RXDATA
CN TRL1
CN TRL0
AGCCAP
R
REF
THLD2
THLD1
Bias Control
Power
Down
Control
Gain Select
AGC Set
AGC Reset
Threshold
Control
BBOUT
DS2
DS1
AND
dB Below
Peak Thld
Ref
Thld
PKDET
Ref
AGC
C
BBO
C
PKD
R
LPF
C
AGC
R
PR
R
PW
R
TH2
R
TH1
20
17
18
14
15
3
9
5
6
4
7
13
11
12
VCC1: Pin 2
VCC2: Pin 16
GND1: Pin 1
GND2: Pin 10
GND3: Pin 19
NC: Pin 8
RREF: Pin 11
CMPIN: Pin 6
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