Antenna tuning for new RF front-end standard

April 04, 2013 // By Graham Prophet
STMicroelectronics' STHVDAC-304MF3 antenna-tuning circuit has a 4-channel output for adjusting up to four tunable BST capacitors in the antenna-matching circuits of multi-band GSM/WCDMA/3G-LTE smartphones. A key feature is support for the MIPI Alliance RF Front End (RFFE), an emerging industry standard that simplifies cellular radio design.

The STHVDAC-304MF3 is controlled via an RFFE-compliant 1.8V interface, and comprises a high-voltage digital-analogue converter (HVDAC) for generating capacitor-tuning voltages from 2V to 20V. Features include a trigger mode for time critical application, and a shutdown mode allowing longer battery life. This new device joins ST’s 3-channel STHVDAC-303, which has a standard SPI host connection. The device is in production in a 0.4mm-pitch, 0.6mm-high, chip-scale package. Pricing is $0.50 (1,000). The datasheet and short video on ST’s STHVDAC-304MF3 antenna-tuning circuit are available at