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Replace two filters with one

The latest advances in Murata’s filter technology have led to development of a new SAW filter whose high power capability means it can be used as a top filter, replacing two interstage filters with a single component. In addition, the filter’s external matching circuit requires just two inductors. This overall reduction in component count minimises a design’s bill of materials and will be of particular benefit to OEMs making wireless consumer devices such as mobile phones.

The new SAW filter (part number SAFEA2G45AC0F00) has a nominal centre frequency of 2450MHz, suitable for Bluetooth and WiFi systems. Its high power capability means it can be used directly after the power amplifier, replacing two separate interstage filters in the transmit and receive paths. The resulting reduction in component count simplifies the design, lowers cost and saves space.

The filter can handle input signal levels of +27dBm for 500 hours at up to 85C, or +24dBm for 5000 hours at up to 85C. Voltage standing wave ratio (VSWR) is typically 1.4, with insertion loss typically 1.7 dB. Operating temperature is -30 to +85C.