RX2A receiver
433MHz
SAW BPF
LNA 1
1
RF in
LNA 2
MIXER
IF1
10.7MHz
10.7MHz IF filter
IF2/Lim
10.7MHz
3
RSSI
10.7MHz
ceramic
discriminator
(f
RF
- 10.7MHz)
Audio LPF
AF
buffer
6
AF out
16
XTAL OSC.
VCO
C
L
R
T
+2.8V
regulated
to circuit
C
T
data
slicer
10kΩ
5
V
cc
7
RXD
Loop filter
Crystal
Phase
26/28MHz detector
(Fixed frequency PLL Osc.)
Low
dropout
regulator
2
RF gnd
4
0V
Figure 4: RX2A Block diagram
Pin description:
RF IN
(pin 1)
50Ω input from the antenna, DC isolated
RF GND
(pin 2)
RF ground pin, internally connected to
the module screen and pin 4 (0V). This
pin should be connected to the RF return
path (coax braid, main PCB ground plane
etc.)
17.5 mm
48 mm
4.5 mm
18.0 mm
RX2A
30.48 mm
Radiometrix
PCB level
1
2
3
4
5
6
7
1 = RF IN
2 = RF GND
3 = RSSI
4 = 0V
5 = Vcc
6 = AF out
7 = RXD
7 holes of 0.7 mm dia. pin spacing 2.54mm
Figure 5: Physical dimensions
RSSI
(pin 3)
Received signal strength indicator with 60dB range. See page 4 for typical characteristics.
0V
(pin 4)
DC supply ground. Internally connected to pin 2 and module screen.
Vcc
(pin 5)
+2.7V to +16.0V DC supply. Max ripple content 0.1V
p-p
. Decoupling is not generally required.
AF out
(pin 6)
Buffered and filtered analogue output from the FM demodulator. Standing DC bias 1.1V approx. External
load should be >10k // <100pF.
RXD
(pin 7)
Digital output from the internal data slicer. The data is a squared version of the signal on pin 6 (AF) and
is true data, i.e. as fed to the transmitter. Output is “open-collector” format with internal 10k pull-up to
Vcc (pin 5).
Radiometrix Ltd, TX2A/RX2A Data Sheet
page 3
RADIOMETRIX [ RADIOMETRIX LTD ]
