TH7107EFC Melexis Inc, TH7107EFC Datasheet - Page 3

• Manufacturer Part Number: TH7107EFC
• Description: IC XMITTER 315/433MHZ 16-SSOP
• Manufacturer: Melexis Inc

Specifications of TH7107EFC

• Rohs Status: RoHS non-compliant
• Frequency: 310MHz ~ 450MHz
• Applications: Alarm and Security Systems, RKE
• Modulation Or Protocol: ASK, FM, FSK
• Data Rate - Maximum: 40 kbps
• Power - Output: -12dBm ~ 2dBm
• Current - Transmitting: 4.8mA ~ 11.5mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 2.2 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-SSOP
• Features: -
• Memory Size: -
• Other names: TH7107; TH7107EFF

1 Theory of Operation
1.1 General
As depicted in Fig.1, the TH7107 transmitter consists of a fully integrated voltage-controlled oscillator (VCO),
a divide-by-32 divider (div32), a phase-frequency detector (PFD) and a charge pump. An external loop filter
at pin LF determines the dynamic behavior of the PLL and suppresses reference spurious signals. The
VCO’s output signal feeds the power amplifier (PA). RF signal power P
P
PS. The open-collector differential output (OUT1, OUT2) can be used to either directly drive a loop antenna
or to be converted to a single-ended impedance by means of a balanced-to-unbalanced (balun) transformer.
For maximum available output power, the differential output should be matched to a load of about 1 k .
Bandgap biasing ensures stable operation of the IC at a power supply range of 2.2 V to 5.5 V.
1.2 Block Diagram
3901007107
Rev. 008
o
= –12 dBm to +2 dBm either by changing the value of resistor RPS or by varying the voltage V
CX1
XTAL
CX2
CKOUT
RO2
RO1
4
8
5
3
div 4
DATA
VCC 10
Fig. 1: Block diagram with external components
XOSC
div32
1
PFD
CF1
LF1
RF1
charge
pump
Page 3 of 16
VCC
CF2
15
16
LF2
VCO
2
SUB
PS
FSK/FM/ASK Transmitter
control
mode
o
PA
can be adjusted in six steps from
9
RPS
VEE
VEE
14
13
OUT2
12
11
OUT1
ENCK
7
ENTX
6
TH7107
315/433MHz
antenna
balun
or
Data Sheet
PS
May/03
VCC
at pin