General Description
The IC is a low power consumption single chip FSK/ASK Transceiver for half duplex low datarate communication in the 868-870MHz band. The IC offers a very high level of integration and needs only a few external components. It contains a highly efficient power amplifier, a low noise amplifier (LNA) with AGC, a double balanced mixer, a complex direct conversion stage, I/Q limiters with RSSI generation, an FSK demodulator, a fully integrated VCO and PLL synthesizer, a tuneable crystal oscillator, an onboard data filter, a data comparator (slicer), positive and negative peak detectors, a data rate detection circuit and a 2/3-wire bus interface. Additionally there is a power down feature to save battery power.

FEATUREs
■ Low supply current (Is = 9mA typ. receive, Is = 12mA typ. transmit mode)
■ Supply voltage range 2.1 - 5.5V
■ Power down mode with very low supply current consumption
■ FSK and ASK modulation and demodulation capability
■ Fully integrated VCO and PLL synthesizer and loop filter on-chip with on chip crystal oscillator tuning
■ I2C/3-wire µController Interface
■ On-chip low pass channel select filter and data filter with tuneable bandwidth
■ Data slicer with self-adjusting threshold and 2 peak detectors
■ FSK sensitivity <-109dBm, ASK sensitivity < –109dBm
■ Transmit power up to +13dBm
■ Datarates up to 64kBit/s Manchester encoded
■ Self-polling logic with ultra fast data rate detection

APPLICATION
■ Low Bitrate Communication Systems
■ Keyless Entry Systems
■ Remote Control Systems
■ Alarm Systems
■ Telemetry Systems
■ Electronic Metering
■ Home Automation Systems