AC-RX Economic Receiver
Product Information
AC-RX Receiver
The AC-RX Receiver is an economic receiver with low consumption,
low voltage supply, and a variable coil. It has been optimized for
use with the HCS KEELOQ decoder/encoder family. The receiver
operates at a working center frequency of 433.92 MHz and has a
voltage supply range of 4.5V to 5.5V. It features a low absorbed
current of 2.5mA to 3mA and a high RF sensitivity of -100dBm. The
receiver also has a square wave output with a frequency of 3KHz and
output voltages that depend on the load applied.
Technical Features
- Working center frequency: 433.92 MHz
- Voltage supply range: 4.5V – 5.5V
- Absorbed current: 2.5mA – 3mA
- RF sensitivity: -100dBm
- Square wave output frequency: 3KHz
- Output low voltage: Gnd+0.4V
- Output high voltage: V (dependent on load applied)
- Switch-on time: 2s
- Operating temperature range: -20°C to +80°C
- Dimensions: 38.1mm x 12.3mm x 5.5mm
Note
- Values have been obtained by applying the test system as per
Fig. 1. - The RF emission measure has been obtained by connecting the
spectrum analyzer directly to RX Pin 3. - Switch-on time refers to the time required by the receiver to
acquire the declared characteristics from the moment power supply
is applied. - Values obtained with a maximum load of 10K applied.
Device Usage
In order to take advantage of the performances described in the
technical specifications and to comply with the operating
conditions, follow the instructions below:
Printed Circuit
- The receiver must be fitted on a double-layer printed circuit,
with vias to the ground planes placed approximately every
15mm. - The circuit must be properly dimensioned, especially in the
antenna connection area if a radiating whip antenna is fitted
(approximately 50mm radius is suggested).
50 Ohm Line
- The 50 Ohm line should be as short as possible.
- For 1mm thick FR4 printed circuits, it should be 1.8mm wide.
For 1.6mm thick FR4 printed circuits, it should be 2.9mm wide. - Keep the line 2mm away from the ground circuit on the same side
and ensure a ground circuit area is present on the opposite
side.
Antenna Connection
- The receiver’s antenna connection can be used as the direct
connection point for a radiating whip antenna. - It can also be used to connect the central wire of a 50 Ohm
coaxial cable. Make sure the braid is welded to the ground in a
close point.
Antenna
A whip antenna, 16.5mm long and approximately 1mm in diameter,
made of brass or copper wire, must be connected to the RF input of
the receiver.
Technical features are subject to change without notice.
AUREL S.p.A. does not assume responsibilities for any damages
caused by the device’s misuse.
AC-RX Receiver
AC-RX
Instruction manual
Economic receiver with low consumption, low voltage supply and variable coil. Optimised characteristic for HCS KEELOQ decoder/encoder family.
Pin-out
38.1
5.5
12.3
Component Side
12 3
7
11 13 14 15
15
7
0.5
2.54
0.25
1
Connections
Pin 2-7-11 Pin 3 Pin 1-15 Pin 13
Ground Antenna +V Test Point
Pin 14
Data Out
GND Connections: Internally connected to a single ground plate 50 impedence antenna connection Connection to the +5V ±0.5V supply positive pole Analog output of the demodulated signal. By connecting an oscillograph the entity and quality of the received RF signal can be seen. Receiver digital output. Apply loads over 10 K
Technical features
Min Tipical Max
Unit
Working centre frequency
433.92
MHz
Voltage supply
4.5
5
5.5
V
Absorbed current
2.5
3
mA
RF sensitivity
-100
dBm
See note 1
-3 dB RF bandwidth
±2
MHz
Square wave output
3
KHz
Output low voltage
Gnd+0.4
V
See note 4
Output high voltage RF spurious emissions in antenna
VS 0.4 -65
V dBm
See note 4 See note 2
Switch-on time
2
s
See note 3
Operating temperature range
-20
+80
°C
Dimension
38.1 x 12.3 x 5.5 mm
Nota1: Values have been obtained by applying the test system as per Fig. 1. Nota2: The RF emission measure has been obtained by connecting the spectrum analyser directly to RX Pin 3. Nota3: By switch-on time is meant the time required by the receiver to acquire the declared characteristics from the very moment the power supply is applied. Nota4: Values obtained with 10K maximum load applied.
Technical features are subject to change without notice. AUREL S.p.A. does not assume responsibilities for any damages caused by the device’s misuse.
AUR°EL S.p.A. Via Foro dei Tigli, 4 – 47015 Modigliana (FC) ITALY Tel.: +390546941124 Fax: +390546941660 http://www.aurel.it – email: [email protected]
Rev. A, 9-01-2003 Pag 1 di 4
AC-RX
Instruction manual
The declared technical features have been verified by applying the following test system:
Fig. 1
RF Generator: 433.92 MHz frequency Out Level 88dBm
MC 145026 Digital encoder
OOK [-2dB] Modulator
AC-RX Pin 3
-10dB Attenuator
Pin 14
MC 145028 Decoder
Code validation
Device usage
In order to take advantage of the performances described in the technical specifications and to comply with the operating conditions which characterize the Certification, the receiver has to be fitted on a printed circuit, considering what follows:
5V Supply voltage
1. The receiver must be supplied by a very low voltage source, safety protected against short circuits. 2. Maximum voltage variations allowed: ± 0.5 V. 3. De-coupling, next to the receiver, by means of a minimum 100.000 pF. ceramic capacitor.
Ground
1. It must surround at the best the welded area of the receiver. The circuit must be double layer, with throughout vias to the ground planes, approximately each 15 mm.
2. It must be properly dimensioned, specially in the antenna connection area, in case a radiating whip
antenna is fitted in it (an area of approximately 50 mm radius is suggested.)
Fig.2 Suggested lay-out for the device correct usage
Technical features are subject to change without notice. AUREL S.p.A. does not assume responsibilities for any damages caused by the device’s misuse.
AUR°EL S.p.A. Via Foro dei Tigli, 4 – 47015 Modigliana (FC) ITALY Tel.: +390546941124 Fax: +390546941660 http://www.aurel.it – email: [email protected]
Rev. A, 9-01-2003 Pag 2 di 4
AC-RX
Instruction manual
50 Ohm line
1. It must be the shortest as possible. 2. 1,8 mm wide for 1 mm thick FR4 printed circuits and 2,9 mm wide for 1,6 mm thick FR4 printed circuits.
On the same side, it must be kept 2 mm away from the ground circuit.
3. On the opposite side a ground circuit area must be present.
Antenna connection
1. It may be utilized as the direct connection point for the radiating whip antenna. 2. It can bear the connection of the central wire of a 50 coaxial cable. Be sure that the braid is welded to
the ground in a close point.
Antenna
1. A whip antenna, 16,5 mm long and approximately 1 mm dia, brass or copper wire made, must be connected to the RF input of the receiver.
2. The antenna body must be keep straight as much as possible and it must be free from other circuits or metal parts (5 cm minimum suggested distance.)
3. It can be utilized either vertical or horizontal, provided the connection point between antenna and
receiver input, is surrounded by a good ground plane.
N.B: As an alternative to the a.m. antenna it is possible to utilize the whip model manufactured by Aurel
(see related Data Sheet ed Application Notes). By fitting whip antennas too different from the described ones, the EC Certification is not assured.
Other components
1. Keep the receiver separate from all other components of the circuit (more than 5 mm). 2. Keep particularly far away and shielded all microprocessors and their clock circuits. 3. Do not fit components around the 50 Ohm line. At least keep them at 5 mm distance. 4. If the Antenna Connection is directly used for a radiating whip antenna connection, keep at least a 5 cm
radius free area. In case of coaxial cable connection then 5 mm radius will suffice.
Technical features are subject to change without notice. AUREL S.p.A. does not assume responsibilities for any damages caused by the device’s misuse.
AUR°EL S.p.A. Via Foro dei Tigli, 4 – 47015 Modigliana (FC) ITALY Tel.: +390546941124 Fax: +390546941660 http://www.aurel.it – email: [email protected]
Rev. A, 9-01-2003 Pag 3 di 4
AC-RX
Instruction manual
Reference Rules
The AC-RX receiver is EC certified and in particular it complies with the European Rules EN 300 220-3 and EN 301 489. The equipment has been tested according to rule EN 60950 and it can be utilized inside a special insulated housing that assures the compliance with the above mentioned rule. The receiver must be supplied by a very low voltage safety source protected against short circuits The use of the receiver module is foreseen inside housings that assure the overcoming of the rule EN 61000-4-2 not directly applicable to the module itself. In particular, it is at the user’ s care the insulation of the external antenna connection, and of the antenna itself since the RF output of the receiver is not built to directly bear the electrostatic charges foreseen by the a.m. rule.
Sensitivity [dB]
Fig.3 Frequency – sensitivity plot
420 -110 -100
-90 -80 -70 -60 -50 -40 -30 -20 -10
0
Frequency [MHz]
430
440
450
Plot was obtained using the test set up as in Fig.1 with variation of frequency and output level of RF generator
Technical features are subject to change without notice. AUREL S.p.A. does not assume responsibilities for any damages caused by the device’s misuse.
AUR°EL S.p.A. Via Foro dei Tigli, 4 – 47015 Modigliana (FC) ITALY Tel.: +390546941124 Fax: +390546941660 http://www.aurel.it – email: [email protected]
Rev. A, 9-01-2003 Pag 4 di 4

















