
Melexis Microelectronic Systems
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 800 MHz to 930 MHz (e.g. for applications in the US 915MHz ISM band).
FEATUREs
❐ Fully integrated, PLL-stabilized VCO
❐ Flexible frequency range from 800 MHz to 930 MHz
❐ FSK through crystal pulling allows modulation from DC to 20 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 independently 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 standard
APPLICATION Examples
❐ Keyless car and central locking
❐ Low-power telemetry
❐ Alarm and security systems
❐ General digital data transmission
❐ General analog audio signal transmission