QFMR5-434 RF Solutions, QFMR5-434 Datasheet - Page 5

• Manufacturer Part Number: QFMR5-434
• Description: MODULE, RECEIVER, SIL, FM
• Manufacturer: RF Solutions

Specifications of QFMR5-434

• Svhc: No SVHC (15-Dec-2010)
• Current Rating: 6mA
• External Depth: 4mm
• External Length / Height: 49mm
• External Width: 17mm
• Frequency: 433.92MHz
• Operating Temperature Max: 80°C
• Operating Temperature Min: -25°C

FM Radio Transmitter & Receiver Modules
Antenna Design
The design and positioning of the antenna is as
crucial as the module performance itself in
achieving a good wireless system range.
following will assist the designer in maximising
system performance.
The antenna should be kept as far away from
sources of electrical interference as physically
possible.
decoupling capacitors should be placed close to
the module.
The antenna ‘hot end’ should be kept clear of any
objects, especially any metal as this can severely
restrict the efficiency of the antenna to receive
power. Any earth planes restricting the radiation
path to the antenna will also have the same effect.
Best range is achieved with either a straight piece
of wire, rod or PCB track @ ¼ wavelength
(15.5cm @ 433.92MHz). Further range may be
achieved if the ¼ wave antenna is placed
perpendicular in the middle of a solid earth plane
measuring at least 16cm radius. In this case, the
antenna should be connected to the module via
some 50 ohm characteristic impedance coax
DS305_2
RF
RF
Figure 3: Antenna Configurations To Be Used
With The QFMT5 & QFMR5 Modules
Helical Antenna
17 turns equally spaced
Whip Antenna
= 5mm (inside)
If necessary, additional power line
April 01
34mm @ 433MHz
15.5cm @ 433MHz
2001 REG No 277 4001, England.
The
Application Circuit
The application circuits show how the QFMT5
transmitter and the QFMR5 receiver can easily be
integrated into a system to form a wireless link.
RSSI Values:
The QFMR5 RSSI output provides a DC output
proportional to the RF input signal. The table
below shows the typical RSSI value depending on
the Rf signal strength.
Figure 5: QFMR5 Receiver Application Circuit
Figure 4: QFMT5 Transmitter Application
1
2
3
4
5
6
7
8
9
A0
A1
A2
A3
A4
A5
A6
A7
VSS
1
2
3
4
5
6
7
8
9
HT12D
A0
A1
A2
A3
A4
A5
A6
A7
VSS
RF Signal Strength / dBm
OSC1
OSC2
HT12E
VDD
D11
D10
DIN
D9
D8
VT
18
17
16
15
14
13
12
11
10
DOUT
OSC1
OSC2
AD11
AD10
VDD
AD9
AD8
TE\
+5V
18
17
16
15
14
13
12
11
10
DATA OUT 4
DATA OUT 3
DATA OUT 2
DATA OUT 1
R
OSC
+5V
-110
-100
1K5
-90
-80
-70
-60
-50
-40
-30
-20
R
OSC
Circuit
ANTENNA
ANTENNA
RSSI / V
Quasar
R 5
tba
1 2
T5 / R5
T5
1 2
Page 5
3 4 5 6 7
3
4 5
+5V
+5V