MICRF004

MICRF004/RF044 Micrel MICRF004 QwikRadio™ Low-Power VHF Receiver Advance Information General Description The MICRF004 QwikRadio™ VHF receiver is a single-chip OOK (on-off keyed) receiver IC for remote wireless applications. This device is a true single-chip, “antenna-in, data-out” device. All RF and IF tuning is accomplished automatically within the IC which eliminates manual tuning production costs and results in a highly reliable, extremely low-cost solution for high-volume wireless applications. The MICRF004 is extremely easy to apply, minimizing design and production costs, and improving time to market. The MICRF004 provides two fundamental modes of operation, fixed and sweep. In fixed mode, the device functions as a conventional superheterodyne receiver with an internal local oscillator operating at a single frequency based on an external reference crystal or clock. Fixed mode is for use with accurately-controlled transmitters utilizing crystal or SAW (surface acoustic wave) resonators. In sweep mode, the MICRF004 sweeps the internal local oscillator at rates greater than the baseband data rate. This effectively broadens the RF bandwidth of the receiver to a value equivalent to conventional superregenerative receivers. This allows the MICRF004 to operate with less expensive LC transmitters without additional components or tuning, even though the receiver topology is still superheterodyne. In this mode the reference crystal can be replaced with a less expensive ± 0.5% ...