STMicroelectronics Antenna Tuner Supports MIPI Alliance RF Front-End Standard
As wireless broadband consumes ever larger amounts of spectrum, engineers are looking for antenna designs capable of working over a wide range of frequencies. One approach is to use tuned antennas. The MIPI Alliance
RF Front End (RFFE) is an emerging industry standard designed to simplify cellular radio design.
The STMicroelectronics STHVDAC-304MF3
has a four channel output for adjusting up to four tunable BST capacitors in the antenna-matching circuits of multi-band GSM/WCDMA/3G-LTE smartphones. It is controlled via an RFFE compliant 1.8V interface. A high-voltage digital to analog converter (HVDAC) provides tuning voltages ranging from 2 to 20 volts. Other features include a trigger mode for time critical applications and a shutdown mode allowing longer battery life.
While this device is designed for the cellular bands, it appears it could also be used on UHF and perhaps even VHF TV bands to improve reception on portable devices with limited space for antennas.