TXM-900-HP-II Linx Technologies Inc, TXM-900-HP-II Datasheet - Page 9

• Manufacturer Part Number: TXM-900-HP-II
• Description: TRANSMITTER RF 900MHZ 8-CHANNEL
• Manufacturer: Linx Technologies Inc
• Series: HP2r

Specifications of TXM-900-HP-II

• Frequency: 902MHz ~ 928MHz
• Applications: ISM, RKE, Security and Fire Alarms
• Modulation Or Protocol: FM, FSK
• Data Rate - Maximum: 50 kbps
• Power - Output: -3dBm ~ 4dBm
• Data Interface: PCB, Through Hole
• Antenna Connector: Through Hole
• Voltage - Supply: 2.17 V ~ 16 V
• Operating Temperature: 0°C ~ 70°C
• Package / Case: SIP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Memory Size: -
• Current - Transmitting: -
• Other names: TXM-900-HP2; TXM-900-HP2

CTS OUTPUT
CHANNEL SELECTION
The Clear-To-Send output is used to indicate to the user’s circuitry when the
transmitter is ready to accept data. This pin can be monitored to allow
transmission to begin immediately upon the transmitter’s synthesizer locking on
frequency.
In a typical application, a micro-controller will raise the PDN line high (powering-
up the transmitter) and begin to monitor the CTS line. When the CTS line goes
high, the micro-controller would start sending data.
In applications where CTS is not used, i.e., an extra I/O pin is not available, the
user’s circuit should wait a minimum of 50mSec after raising the PDN pin high
before transmitting any data.
In applications where remote-control encoders are used, the data is being sent
redundantly and there is no need to monitor the CTS pin or to wait a fixed time.
The HP-II transmitter module
features eight user-selectable
c h a n n e l s. The channel of
operation is determined by the
state of pins CS0-CS2. Figure
17 shows a channel-selection
table based on the pins’states.
The on-board microprocessor
p e r fo rms
functions. This frees the user
from complex progra m m i n g
requirements and allows for manual channel selection via switches in product
designs where a microprocessor is not used.
NOTE:
There are some timing requirements the user must observe when
periodically powering-up the transmitter.
The on-period is determined by the start-up procedure and requires the
user to leave the transmitter on for 8-12 mSec.After this time the transmitter
is stable and ready to transmit valid data.
The off-period is determined by the discharge rate of the internal bypass
capacitors. The capacitors must fully discharge to ensure that subsequent
power-ups will reliably restart the microprocessor. This minimum time
should be no less than 1 mSec.If the transmitter is not reliably starting after
power-up, this time should be increased.
all
READ THIS IF YOU ARE GOING TO PERIODICALLY
POWER DOWN THE TRANSMITTER!!
PLL
loading
Figure 17: Channel Selection Table
CS2
0
0
0
0
1
1
1
1
CS1
0
0
1
1
0
0
1
1
CS0
0
1
0
1
0
1
0
1
Channel
5
6
7
0
1
2
3
4
Frequency
921.37
903.37
906.37
907.87
909.37
912.37
915.37
919.87
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