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RF5745

DS120214

7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical

support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.

Theory of Operation

The RF5745 is an integrated front-end module (FEM) for high performance ZigBee® (802.15.4) and WiFi (802.11b/g) applica-

tions in the 2.4GHz to 2.5GHz ISM band. The FEM addresses the need for aggressive size reduction by integrating 50

 match-

ing networks to all RF ports and minimizing the number of external components. The FEM has integrated ZigBee® power

amplifier, LNA, power detector, and some TX filtering. Also it is capable of switching between WiFi RX, WiFi TX, and simultane-

ous WiFi/BT Receive modes. The device is manufactured on GaAs HBT/pHEMT processes and is provided in a

3.00mmx3.00mmx0.45mm 16-pin QFN package. This module meets or exceeds the front-end system requirements for

802.15.4 and 802.11b/g applications.

For best performance, the evaluation board layout should be copied as close as possible in particular the ground vias and

bypassing components. Other configurations may work, but the design process is much easier and quicker if this recommen-

dation is followed. Gerber files of the evaluation board can be provided upon request. The supply voltage lines should present

The RF5745 is a very easy part to implement, but care on circuit layout and component selection is always advisable when

designing circuits that operate at 2.5GHz. Please contact RFMD Sales or Application Engineering for additional data and guid-

supply to simplify bias requirements.

802.11b/g and ZigBee® Transmit Path

The RF5745 has a typical gain of 31dB from 2.4GHz to 2.5GHz. This FEM is capable of delivering a typical output power of

24dBm to 25dBm when operating under the IEEE802.15.4 conditions. It is also capable of delivering 17dBm typical output

power with a standard IEEE802.11g waveform and 20dBm with a standard IEEE802.11b waveform. Current control optimiza-

Out of Band Rejection

The RF5745 contains basic filtering components for the transmit path. Due to space constraints inside the module, filtering is

limited to a few resonant poles. Additional filters may be needed outside the module depending upon the end-user's applica-

tion.

Receive Path

While on receive mode, the RF5745 has a typical gain of 10dB and minimum insertion loss for the BT path. The RX port return

loss is typically around 10dB. Depending on the application, if higher out of band rejection is needed beyond what the RF5745

can achieve, then additional external filters may be added. The RF5745 is designed so that the SP3T may act as a 3dB splitter

when placed in WiFi RX and BT RX mode simultaneously. See logic control table for proper settings.