The Melexis TH72001 FSK transmitter IC is designed for applications in the 315 MHz industrial-scientific-medical (ISM) band. It can also be used for any other system with carrier frequencies ranging from 290 to 350 MHz. The transmitter's carrier frequency is determined by the frequency of the reference crystal fref. The integrated phase-locked loop (PLL) synthesizer ensures that carrier frequencies, ranging from 290 MHz to 350 MHz, can be achieved. This is done by using a crystal with a reference frequency according to: fref = fc/N, where N = 32 is the PLL feedback divider ratio.
Features
Application examples
Fully integrated PLL-stabilized VCO
Frequency range from 290MHz to 350MHz
Single-ended RF output
FSK through crystal pulling allows modulation from DC to 40kbit/s
High FSK deviation possible for wideband data transmission
Wide power supply range from 1.95V to 5.5V
Operating temp. range from -40°C to +125°C
Very low standby current
On-chip low voltage detector
High over-all frequency accuracy
FSK deviation and center frequency independently adjustable
Adjustable output power range from -10dBm to max. +11dBm
Adjustable current consumption from 3.2mA to 10.3mA
