Avago’s ACFM 7101 quintplexer module

Avago’s ACFM 7101 quintplexer module

The ACFM-7101 quintplexer from Avago Technologies (San Jose, CA) integrates a US PCS duplexer, a cellular band duplexer, and a GPS band filter in a single package with a single antenna port. The innovative part was selected as a 2006 Product of the Year so we asked the company to go beyond the specs to find out what makes this product tick.

Significant achievements

The device eliminates the need for antenna switching or diplexers. Low Tx insertion loss reduces current drain from power amplifiers to extend battery life and talk time. The quintplexer enhances receiver sensitivity and dynamic range with low Rx insertion loss, high rejection of Tx signals at Rx ports, and high rejection of Tx-generated noise in the receive bands.

Design hurdles

Technical challenges included designing antenna-matching networks with minimal impact on in-band insertion loss; modeling (EM simulation) of full interaction between traces on high-density substrate; and matching the phone PCB layout for optimal (no crossed traces) pin-out while maintaining electrical performance of discrete components. We hoped that the five filters would not load each other negatively, and were able to achieve the reverse, with the filter set being better than the individual filter performances.

The engineering effort

The part took 18 months from inception to product launch, with project teams based out of San Jose, CA; Penang, Malaysia; and Fort Collins, CO. Although it was spread across three sites, the team was small enough to allow good interaction between all members.

Application areas?

Used in cell phones from both Verizon and Sprint, the device quickly hit a shipment rate of over one million per month after only four months since its limited release.

The platform for future generations of Avago multiplexers, the company recently introduced the ACFM-7102, which adds simultaneous GPS functionality.

Ralph Raiola