nRF902 is a single-chip transmitter for the 868 MHz ISM band, designed to complywith the ETSI specification I-ETS 300 220. Using nRF902 both FSK and ASKmodulation is possible. The transmitter consists of a fully integrated frequencysynthesiser, a power amplifier, a crystal oscillator and a modulator. Few externalcomponents are required: a 13.567 MHz crystal, two resistors and some decouplingcapacitors. Due to the use of the crystal-oscillator stabilised frequency synthesiser,frequency drift is much lower than in comparable SAW-resonator based solutions.Output power is easily programmable by use of an external resistor. Currentconsumption is very low, only 9 mA at an output power of –10dBm. Built-in Clockand Power Down modes makes power saving and duty-cycling easily realisable.