General Description

The IC is a low power consumption single chip FSK/ASK Transceiver for half duplex low datarate communication in the 315MHz 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

= 13mA 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

– Self-polling logic with ultra fast data rate detection