Murata Manufacturing Co., Ltd. has started the mass production of transmission modules with a low current consumption for cell phones and smartphones.
These are the world's smallest transmission modules whose mounting footprint has been slashed by 50% compared with previous products, and their sizes have been achieved by the fabrication of a monolithic construction through the use of LTCC circuit boards*1. By incorporating a stabilizer*2 (isolator function) , the amount of current consumed when conditions change in the environments where cell phones and smartphones are used has been successfully cut by up to about 20%. This accomplishment will contribute to simplifying the design of the cell phones and smartphones.
In their support of the LTE standard and their adoption of more and more functions, cell phones and smartphones have tended in recent times to incorporate more and more components and consume higher and higher levels of current. Against this backdrop, demands have been voiced that the designs be more compact and that the current consumption be reduced in the high-frequency circuit areas that are indispensable for cell phones and smartphones. In order to satisfy these demands, Murata Manufacturing was the first company in the world to develop transmission modules for cell phones  that provide a SAW filter*3, power amplifier*4 and stabilizer in a single integrated package. In fact, the company started mass producing these modules in July 2011, and they have been the target of high critical acclaim. This time, using LTCC circuit boards for these transmission modules, the surrounding chip components (couplers, capacitors and inductors) have been incorporated into the monolithic structural parts to successfully give the modules a super-small size. Furthermore, by incorporating a stabilizer (isolator function) , transmission modules that boast a low current consumption have been created.
- The high level of integration (characterized by the integration of the SAW filter, power amplifier and stabilizer into a single package) achieved using LTCC circuit boards has resulted in a reduction of the mounting footprint (by 50% compared with previous products) .
- By incorporating a stabilizer (isolator function) , the levels of the current consumed when conditions change in the environments where cell phones and smartphones are used have been reduced (by up to 20% or so) .
- Also, by incorporating the stabilizer (isolator function) , the quality of the phone calls can be maintained regardless of the antenna status.
- The new modules help to shorten the time taken to design the products that use them (products can be designed without taking the matchup with the SAW duplexers into account) .
- Packaged products that provide both dual band (Band 1/Band 5+18) support and single band (Band 11) support are now available commercially. (* Murata is working toward achieving further frequency extension. )
Cell phones and smartphones
- Modules with Dual Band support: 4.5 (typ.) x 5.5 (typ.) x 1.0mm (max.)
- Modules with Single Band support: 3.0 (typ.) x 5.5 (typ.) x 1.0mm (max.)
The transmission modules have been mass produced at Okayama Murata Manufacturing Co., Ltd. since August 2012 (at a monthly pace of 300,000 pieces) .
Co-fired Ceramics) :
|Normal electronic ceramics are fired at high temperatures above 1500°C, but the firing temperature for LTCC is below 1000°C, which is low, making it possible to use silver and copper with a low conductor resistance for the wiring of the layers inside the circuit boards.|
(Magnetic Stabilizer) :
|This load-resistant element is a magnet used in an isolator. It controls fluctuation in characteristics caused by changes in impedance (deviation of antenna characteristics) that occur when the user's hand, metal or other material nears the antenna.|
|*3||SAW filter:||An element using the characteristics of piezoelectric bodies to get an electrical signal of a certain frequency band.|
|*4||Power amplifier:||A semiconductor that amplifies a high-frequency signal in a mobile phone, etc. when that signal is transmitted.|