TH7108

868/915MHz

FSK/FM/ASK Transmitter

3901007108

Page 1 of 14

Data Sheet

Rev. 008

May/03

Features

! Fully integrated, PLL-stabilized VCO

! Frequency range from 850 MHz to 920 MHz

! FSK through crystal pulling allows modulation

from DC to 40 kbit/s

! High FSK deviation possible for wideband data

transmission

! ASK achieved by on/off keying of internal

power amplifier

! FM possible with external varactor

! Wide power supply range from 2.2 V to 5.5 V

! High over-all frequency accuracy

! Very low standby current

! Adjustable output power range from

-15 dBm to +1 dBm

! Adjustable current consumption from

6.2 mA to 12.5 mA

! FSK deviation and center frequency independ-

ently adjustable

! Differential output well-suited for loop antenna

! External clock available for µC drive,

down to 1.9 V supply

! ”Clock only” mode

! Conforms to EN 300 220 and similar standards

Ordering Information

Part No.

Temperature Code

Package Code

TH7108

E (-40 C° to 85 °C)

FC (QSOP16)

Application Examples

Pin Description

! Keyless car and central locking

! Low-power telemetry

! Alarm and security systems

! General digital data transmission

! General analog audio signal transmission

General Description

The TH7108 FSK/ASK/FM transmitter IC is designed for applications in the European 868MHz industrial-

scientific-medical (ISM) band, according to the EN 300 220 telecommunications standard. It can also be

used for any other system with carrier frequencies ranging from 850 MHz to 920 MHz (e.g. for applications

in the US 915MHz ISM band).

The integrated PLL synthesizer ensures that each RF value, ranging from 850 MHz to 920 MHz, can be

back divider ratio.

LF1

LF2

RO2

DATA

SUB

OUT1

VEE

VCC

TH7108

1

2

3

4

16

15

14

13

5

6

7

8

12

11

10

9

ENTX

RO1

CKOUT

ENCK

OUT2

PS

VCC

VEE