TH72031KDC Melexis Inc, TH72031KDC Datasheet - Page 6

• Manufacturer Part Number: TH72031KDC
• Description: 868/915 MHZ, FSK TRANSMITTER
• Manufacturer: Melexis Inc

Specifications of TH72031KDC

• Frequency: 868MHz, 915MHz
• Applications: Alarm and Security Systems, RKE
• Modulation Or Protocol: FSK
• Data Rate - Maximum: 40 kbps
• Power - Output: -11dBm ~ 9dBm
• Current - Transmitting: 5.1mA ~ 13.4mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 1.9 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Memory Size: -
• Other names: Q3477881B

2.7 Mode Control Logic
The mode control logic allows two different
modes of operation as listed in the following
table. The mode control pin ENTX is pulled-
down internally. This guarantees that the whole
circuit is shut down if this pin is left floating.
2.8 Timing Diagrams
After enabling the transmitter by the ENTX signal, the power amplifier remains inactive for the time t
transmitter start-up time. The crystal oscillator starts oscillation and the PLL locks to the desired output fre-
quency within the time duration t
and then the RF carrier can be FSK modulated.
3901072031
Rev. 010
RF carrier
FSKDTA
LOCK
ENTX
Fig. 5:
on
high
high
high
low
low
low
. After successful PLL lock, the LOCK signal turns on the power amplifier,
Timing diagram for FSK modulation
t
on
Page 6 of 20
ENTX
0
1
TX standby
TX active
Mode
t
FSK Transmitter
TH72031
868/915MHz
Description
TX disabled
TX enable
Data Sheet
Jan/09
on
, the