At Electronica 08 in Munich Germany, Peregrine Semiconductor Corporation announced a new approach to mobile antenna tuning. Called DuNE™ technology, it is a patent-pending design methodology that uses the company's UltraCMOS™ process and HaRP™ technology. The result is a single-die tunable capacitor circuit, which the company refers to as a digitally tunable capacitor (DTC), that reportedly meets the demands for power handling, linearity, power consumption, and integration for antenna tuning in cellular and mobile applications.
The space available for the mobile system antenna is shrinking at a rapid rate. As antennas are wrapped and repathed, they lose efficiency. Some of this lost performance can be recovered with antenna tuning, in which the system uses dynamic impedance tuning techniques to optimize the antenna performance for both the frequency of operation and the environmental conditions. That's what Peregrine's DuNE is designed to come in.
The first devices in the DuNE DTC portfolio are designed to meet the broadband requirements for DVB-H and ISDB-T mobile TV; multi-mode, multi-band GSM/WCDMA cellular handsets; and the power handling requirements for interoperability between the two applications.
Peregrine's single-die DuNE DTCs integrate high-Q tunable capacitors (Q=40 to 80 at 1-2 GHz) with a built-in low-voltage serial interface, in a chip-scale package offering a footprint that is 5 times smaller than competing technologies. Typical capacitance values range from 0.5pF to 10pF, with typical tuning ratios ranging from 3:1 to 6:1 with 5 bits or 32 states of resolution. In addition to >+38 dBm of power handling in 50 Ohm, DuNE DTCs feature high linearity (IP3 > +65 dBm) and switching speed of better than 5s.
When the DVB-H antenna is embedded in the GSM handset, the tunable element for DVB-H antenna tuning needs to be able to handle high levels of coupled GSM power without shift in capacitance or causing nonlinearities. Typically better than +26dBm of linear power handling is required to meet GSM/DVB-H interoperability requirements. Peregrine's new DuNE DTCs have been designed for 5 bits of resolution or 32 tuning states, which provides the level of fine resolution that is required to tune the antenna across the entire mobile TV band. As well, DuNE Technology enables a Q = 40″70 at 470 to 862 MHz for a 1.36 to 6.3pF (4.6:1) tunable capacitor. The current consumption is 11 uA at +2.75 V, while meeting the stringent power handling requirements of better than +28dBm and IIP3 of better than +62dBm.
Individual DTC devices are planned for release during 2009, beginning with the DTCs for mobile TV which will be offered in a 2x2mm 8-pin DFN package. Pricing will be volume dependent and is available by contacting Peregrine at firstname.lastname@example.org.
Visit www.psemi.com for more information.