The Melexis TH72011 FSK transmitter IC is designed for applications in the European 433 MHz industrial-scientific-medical (ISM) band, according to the EN 300 220 telecommunications standard. It can also be used in other countries with similar standards like FCC part 15.231. 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 380 to 450 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 380MHz to 450MHz
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 -11dBm to max. +10dBm
Adjustable current consumption from 3.4mA to 10.6mA
