Peregrine Semiconductor’s new digitally tunable capacitor is designed to meet high-performance demands for antenna tuning in cellular and mobile applications. Based on the company's DuNE technology, Peregrine's DTCs meet the broadband requirements for DVB-H and ISDB-T mobile TV as well as multimode, multiband GSM/WCDMA cellular handsets. They can also handle the power requirements for interoperability between the two applications.
Broadband reception is directly related to antenna and handset physical size; any antenna mismatch degrades range and reception quality. Designers typically have two choices: an internal antenna that may not perform well or an external whip antenna that customers won't like. One solution to the dilemma is a “tunable” internal antenna that covers a narrow section of the bandwidth and can be “retuned” as the receive channel changes.
DuNE Technology for mobile TV is designed for applications such as DVB-H and ISDB-T that need broadband reception and deliver good coverage to an already complex system in a small space.
Peregrine’s new DuNE DTCs are designed for 5 bits of resolution or 32 tuning states, providing the fine resolution needed to tune the antenna across the entire mobile TV band. DuNE Technology enables a Q=40–70 at 470MHz-862MHz for a 1.36 to 6.3pF (4.6:1) tunable capacitor. Current consumption is only 11 µA at +2.75 V, while meeting the stringent power handling requirements of better than +28dBm and IIP3 greater than +62dBm.
Individual DTC devices are planned for release during 2009, beginning with the DTCs for mobile TV in a 2mm by 2mm eight-pin DFN package.
