World's smallest BAW filter
25 July 2007
Circuit & System Protection
In the market for GSM capable products, modularisation of RF (radio frequency) components is continually progressing, not least of all filters.
Currently, multipackage modules containing RF IC plus a filter are under development. In order to support such modules, the mould must be of a high tolerance and the filter device must have reliability as high as that of the IC. By its very nature, the SAW (surface acoustic wave) filter requires a structure to maintain the cavity space and therefore it is considerably difficult to achieve downsizing and low-profiling of such a device, whilst fulfilling all the above requirements. In an effort to overcome this challenge, the industry has been engaged in the development of a filter utilising FBAR (film bulk acoustic resonator) technology, however there exist many issues with this technology. For instance, the difficulty of realising an unbalanced-input/balanced-output type filter.
Now, Murata has successfully developed a simple, planar-type device by adopting the BAW (boundary acoustic wave), designated the SAFAM series. High tolerance and high reliability of the mould and IC have been achieved, enabling the commercialisation of a filter with all the characteristics of a SAW filter, and is claimed by the manufacturer to be the world's smallest filter.
The filter measures only 0,8 mm x 0,6 mm x 0,365 mm, which is a 69% reduction in surface area compared to other conventional products. As for the terminal area, lead-free solder BGA (ball grid array) is used since it is most suitable for high-density packaging.
When mounting the conventional SAW filter on the IC embedded module, module inspections such as addition of an under-fill were required in order to achieve reliability as high as the IC. However, as this filter is a highly reliable device, the module inspection process can be simplified and the development period may be shortened.
This filter is compliant with GSM850, GSM900 (EGSM), GSM1800 (DCS) and GSM1900 (PCS).
Further reading:
EMC limits and levels
Altron Arrow
Editor's Choice Circuit & System Protection
As soon as electronics and electrical systems started interfering with each other, the world had to come to some consensus. Considering physics is universal and does not care about what country electrical/electronic products are used in, it should be the same everywhere, right? It is nearly there, but not quite.
Read more...
Clearing the Static: The importance of cleaning in ESD control
Circuit & System Protection
The proper cleaning of ESD-safe areas and equipment such as workstations, floors, mats, trays, and tools using specialised antistatic cleaners is vital to prevent ESD damage.
Read more...
Safety relay for explosive areas
IOT Electronics
Circuit & System Protection
Phoenix Contact has expanded its safety portfolio with the new PSR-MC35-EXI safety relay module, specifically engineered for use in potentially explosive environments.
Read more...
Clearing the Static: Ensuring effective ESD control
Actum
Circuit & System Protection
To maintain reliable electrostatic discharge control, regular testing and accurate measurement are essential, with grounding products and ESD testing equipment being vital.
Read more...
Clearing the Static: The importance of ESD audits
Actum
Circuit & System Protection
An ESD audit is the first step in establishing an effective static control programme in the workplace, and will help identify vulnerable areas and potentially hazardous static zones that require improvement.
Read more...
EMI shielding materials application guide
Circuit & System Protection
TE Connectivity’s shielding solutions include electrically conductive elastomers, gaskets, knitted wire mesh, oriented wire, EMI shielding ventilation panels, shielded window, cable shielding and shielding components.
Read more...
Clearing the Static: ESD containers and packaging
Actum
Circuit & System Protection
Vacuum forming ESD
Electronic components can be damaged by electrostatic discharges. To protect against such damage, electronic assembly parts are often transported or stored in vacuum formed component
...
Read more...
Electrostatic discharge chairs
Actum
Circuit & System Protection
An ESD chair forms an integral part of grounding within the electrostatic discharge protected area to prevent potential damage to products.
Read more...
Conductive ESD footwear
Actum
Circuit & System Protection
Conductive ESD footwear is used in conjunction with other grounding devices, such as a wrist strap, cord, and ESD surface mats, to provide a continuous path to ground.
Read more...
Clearing the Static: The importance of cleaning in ESD control
Actum
Circuit & System Protection
To prevent Electrostatic Discharge (ESD) damage to sensitive electronic assemblies and components, all production, handling, packaging, and storage must take place in an ESD-protected environment.
Read more...