TH71071

 Fully integrated, PLL-stabilized VCO
Flexible frequency range from 310 MHz to 450 MHz
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-12 dBm to +2 dBm
 Adjustable current consumption from 4.8 mA to 11.5 mA
 Differential output well-suited for loop antenna
 Conforms to EN 300 220 and similar standard

 Keyless car and central locking
 Low-power telemetry
 Alarm and security systems
 General digital data transmission
 General analog audio signal transmission
 Local oscillator signal generation

The TH71071 ASK transmitter IC is designed for applications in the European 433MHz industrialscientific-medical (ISM) band, according to the EN 300 220 telecommunications standard. TH71071 can also be used for any other system with carrier frequencies ranging from 310 MHz to 450 MHz (e.g. for applications in the US 315MHz ISM band).

The transmitter TH71071's carrier frequency f_c is determined by the frequency of the reference crystal f_ref that is used. The integrated PLL synthesizer ensures that each RF value, ranging from 310 MHz to 450 MHz,can be achieved by using a crystal with reference frequency according to: f_ref = f_c/N, where N = 32 is the PLL feedback divider ratio.