STMicroelectronics has developed a tunable chip that can avoid dropped calls and increase battery life. The new range of highly miniaturised adaptive devices has been designed to dynamically optimise handset antenna performance. The ParaScan Tunable Integrated Capacitors (STPTIC) are electrically adjustable to maintain efficient transfer of energy from the handset amplifier to the antenna under various operating conditions. The STPTIC helps maximise radiated RF power for better call performance, overcoming the challenges of use in multiple frequency bands, when the handset is held close to the user’s ear or when it is moved away from the head, while minimising amplifier power consumption and extending battery life.
Unlike some alternatives that typically contain multiple switched capacitors, the STPTIC allows capacitance to be adjusted smoothly, without steps, for greater precision. The STPTIC is also smaller, combining a single, variable capacitor with control circuitry using ST’s Integrated Passive and Active Device (IPAD) technology.
“Our latest and most advanced STPTIC family now delivers an even more compelling option for future 4G LTE handsets, which will demand high wireless performance for reliable voice and high-speed data communications with longer battery life” said Ricardo De-Sa-Earp, Group VP and General Manager, Application-Specific Discretes & IPAD Division. “Two of the world’s top five handset manufacturers have already chosen this technology for antenna matching in their current handsets.”
The STPTIC family uses the most advanced generation of ParaScan Barium Strontium Titanate (BST) variable-capacitor technology. These devices meet the demands of wireless system designers by displaying high Q factor at frequencies up to 2.7 GHz, more than 3:1 capacitance change with varying control voltage, and stable performance over the specified temperature range. Devices are easy to design-in, requiring only minimal external components, and have high power capability meeting the requirements of the GSM standard.