RF sub-modules keep mobile devices small as Wi-Fi complexity and speed increase

Murata has begun production of its LMFE3NFB-Jxx series RF sub-modules for Wi-Fi applications. Using proprietary technology, the sub-modules feature a smaller front-end circuit in order to incorporate the Wi-Fi function. This enables a reduction of the component’s surface mount area and a decrease in its contact points in comparison with circuits that use a discrete structure. Wi-Fi is a standard function on smartphones these days, and the supporting frequency band increasingly uses the 5GHz band rather than just the former ISM 2.4GHz band. Additionally, transmission speeds have improved with the recent communications methods use of spatial multiplexing, and investigations into the use of a 2x2-MIMO structure with high-end smartphones have begun. However, accompanying these trends there is concern regarding an increase in front end circuit complexity, additional contact points, and greater surface mount area when considering former structures. To address this the company has implemented its proprietary monolithic ceramic technology and semiconductor design technology to create an RF sub-module that incorporates the structural components required by the front-end circuit. This greatly reduces the component mounting area and decreases the component contact points compared to circuits using the previous discrete structure. It also saves space for customers’ own designs, contributes to efficient use of design resources and a reduction of product development cycles. The tiny sub-modules measure just 3mm x 3mm x 0.9mm maximum. Aimed at mobile devices such as smartphones and tablet PCs, the sub-modules are compliant with Wi-Fi 2.4GHz, 5GHz, IEEE802.11a/b/g/n/ac and incorporate the required structural elements such as PA, LNA, RF switch, filter, duplexer and coupler. They are also compatible with the Qualcomm Atheros WCN3990 dual-band Wi-Fi and Bluetooth connectivity chip set.