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RF5325

DS110618

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 RF5325 provides an integrated solution for WiFi 802.11 b/g/n and Bluetooth® systems. This single package Front End

Module (FEM) solution integrates the Power Amplifier (PA), Power Detector Coupler, and harmonic filtering for the transmit side.

The integrated SP3T switch is capable of simultaneous operation in WiFi and Bluetooth® receive modes by setting two of the

switch branches to a logic control "high."

The integrated harmonic filtering and matching of the RF5325 facilitates deployment on the customer's board by offering 50



interface at all RF ports. For best results, the board layout from the evaluation board should be copied as closely as possible in

particular the ground configuration underneath the FEM and around the RF traces and decoupling capacitors. There is an indi-

cator pin labeled P1 ID that should be left as a no-connect on the PCB. This pin is directly connected to the ground pad of the

IC. For best performance it is recommended that voltage and RF lines do not cross under this pin. Gerber files of RFMD PCBA

designs can be provided upon request.

The RF5325 FEM can be connected directly to the battery without additional voltage regulators. This FEM requires a single

WiFi Transmit Path

The RF5325 has a typical gain of 28dB from 2.4GHz to 2.5GHz, and delivers 18dBm typical output power under 54Mbps

OFDM modulation and 20dBm under 1Mbps 11b modulation. The operating voltage range to meet full specifications is from

3.0V to 4.5V. Current control optimization for the 802.11b/g/n systems is provided through one bias control input pin (VREG).

Out of Band Rejection

The RF5325 contains basic filtering components to produce bandpass responses for the transmit path. Due to space con-

straints inside the module, filtering is limited to a few resonant poles. Additional filters may need to be added outside the mod-

ule depending upon the end-user's application.

WiFi and Bluetooth® Receive Paths

The 802.11b/g/n and Bluetooth® paths are designed to interface in a 50

 impedance environment to minimize insertion

loss. The single-ended ports provide a nominal insertion loss of 0.5dB and a VSWR of 2:1. The RF5325 is designed so that the

SP3T switch allows for simultaneous operation of WiFi and Bluetooth® receive signals (refer to switch control table settings). In

this configuration, the SP3T switch acts as a 3dB splitter adding approximately 3dB of loss to each of the receive paths.