The Si4311/12/13 RF receivers offer a simple, single-ended radio implementation over the 240–960 MHz frequency range. A receive sensitivity of up to –118 dBm enables the creation of communication links with an extended range. The Si431x RF receivers offer excellent receiver performance in cost-sensitive radio applications. The Si431x RF receivers provide designers with advanced features to enable low system power consumption by offloading a number of RF-related activities from the system MCU allowing for extended MCU sleep periods.
Additional features, such as an automatic wake-up timer, 64-byte RX FIFO and a preamble detection circuit, are available.
The Si431x devices digital receive architecture features an ADC and DSP-based modem that performs the radio demodulation and filtering for increased performance. The high integration of the Si431X RF receivers reduces the external BOM to two antenna matching components, a crystal and a bypass capacitor while removing the requirement for expensive RF SAW and IF ceramic filters.
The Si431x RF receivers are designed to work with a microcontroller, crystal, and a few passives to create a very low-cost system. Voltage regulators are integrated on-chip, which allows a wide range of operating supply voltage conditions from +1.8 to +3.6 V.
A standard 4-pin SPI bus is used to communicate with the microcontroller. Three configurable general-purpose I/Os are also available. Minimal antenna matching is required allowing the use of a single ac coupling capacitor, which simplifies the system design and lowers the solution cost.