• Complete receiver on a chip
• -109dBm sensitivity, 1kbps, and BER 10-2
• Image rejection mixer
• 850MHz to 950MHz frequency range
• Low power, 9mA @ 868MHz, continuous on
• Data rates to 10kbps (Manchester Encoded)
• Auto polling (sleep mode, current < 0.1 mA)
• Analog RSSI output
• Programmable “low sensitivity” mode
• No IF filter required
• Excellent selectivity and noise rejection
• Low external part count
• Additional functions programmed through serial interface

The MICRF221 is a third generation QwikRadio^® receiver, offering all the benefits of Micrel's earlier QwikRadio products with significant improvements, including: enhanced sensitivity, automatic duty-cycle feature and RSSI output.

The MICRF221 is a super-heterodyne receiver, designed for OOK and ASK modulation. The down-conversion mixer also provides image rejection.

The MICRF221 receiver provides a SLEEP Mode for duty-cycle operation and an enhanced, customer programmable "WAKE" function. These features are further combined into a wholly integrated "self-polling" scheme that is ideal for low and ultra-low power applications, such as RKE and RFID

All post-detection data filtering is provided on the MICRF221 receiver. Any one of four filter bandwidths may be selected externally by the user in binary steps, from 1.25kHz to 10kHz. The user needs only to program the device with a set of easily determined values based on data rate, code modulation format, and desired duty-cycle operation.