SI4421 - Universal ISM Band FSK Transceiver

Silicon Labs’ Si4421 is a single chip, low power, multi-channel FSK transceiver designed for use in applications requiring FCC or ETSI conformance for unlicensed use in the 433, 868 and 915 MHz bands.

• a completely integrated PLL for easy RF design, and its rapid settling time allows for fast frequency-hopping, bypassing multipath fading and interference to achieve robust wireless links. The PLL’s high resolution allows the usage of multiple channels in any of the bands. The receiver baseband bandwidth (BW) is programmable to accommodate various deviation, data rate and crystal tolerance requirements. The transceiver employs the Zero-IF approach with I/Q demodulation. Consequently, no external.