CMD-KEY4-433 Linx Technologies Inc, CMD-KEY4-433 Datasheet - Page 4

• Manufacturer Part Number: CMD-KEY4-433
• Description: XMITTER KEYFOB 433MHZ 4 BUTTON
• Manufacturer: Linx Technologies Inc

Specifications of CMD-KEY4-433

• Function: Transmitter
• Modulation Or Protocol: ASK, OOK
• Frequency: 433MHz
• Applications: General Remote Control, Garage Opener, RKE
• Interface: Handheld, 4 Button
• Features: 750 ft. Operating Distance
• Voltage - Supply: 2.1 V ~ 3.6 V
• Package / Case: Keyfob
• Board Size: 56.6 mm x 34.8 mm x 11.4 mm
• Minimum Operating Temperature: - 40 C
• Supply Voltage (min): 2.1 V
• Product: RF Modules
• Maximum Frequency: 433.92 MHz
• Supply Voltage (max): 3.6 V
• Supply Current: 3.4 mA
• Maximum Operating Temperature: + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Sensitivity: -
• Data Rate - Maximum: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: Q2235210

RECEIVERS
TYPICAL APPLICATIONS
Page 6
There are four options for receivers within the Linx
product line. The first option is to use one of the OEM
Function Modules, such as the Relay Module or the AC
Wall Module. These items are also pre-certified and
can be immediately included in a product.
The other options are to use one of the Linx receiver
modules. The signal sent by the Keyfob transmitter can
be received by the LR Series receiver module or the LT
Series transcever module. These modules can be
connected to the Holtek HT658 decoder to decode the
signal, or a custom microcontroller can be programmed
to decode it and take specific action.
The KH2 Series offers a slightly simpler solution by
combining the LR Series receiver and the HT658
decoder in a single package.
When a button is pressed on the transmitter, a
corresponding line on the decoder will go high (as long
as the addresses match). This can then be connected
to whatever circuitry is required by the application.
Application Note AN-00300 discusses in detail how to
set the addresses on all of the units. Data guides for all
of the receivers, the HT640 encoder, and the HT658
decoder can be found on the Linx Technologies
website, www.linxtechnologies.com.
The outstanding sensitivity of the LR
Series receiver offers the best range
when combined with the Keyfob
transmitter. When using the LR
Series receiver, the Holtek HT658
decoder chip should be connected
to decode the received signal. This
decoder has ten address lines that
must match the Keyfob address
lines. A DIP switch is commonly
used to set these, but they can also
be hardwired. As long as the
address lines match, when a button
on the Keyfob is pressed, a
corresponding data line on the
decoder (D0-D4) will go high. These
data lines can then be connected to
external
whatever function is required by the
application.
circuitry
to
perform
Figure 6: LR Receiver and HT658 Schematic
VCC
R1
390k
GND
GND
1
2
3
4
5
6
7
8
10
11
12
RXM-LR
1
2
3
4
5
6
7
8
9
NC
NC
NC
GND
VCC
PDN
RSSI
DATA
HT658
D1
D2
D3
D4
D5
D6
D7
VT
DIN
OSC1
OSC2
GND
VCC
D0
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
ANT
GND
NC
NC
NC
NC
NC
NC
24
23
22
21
20
19
18
17
16
15
14
13
16
15
14
13
12
11
10
9
VCC
GND
GND
Figure 7: CMD-KEY#-*** Schematic Diagram
Page 7
Page 7