2bit digital step attenuator suits 4G LTE apps

Peregrine Semiconductor Corp. has introduced the PE43204 2bit UltraCMOS digital step attenuator (DSA) suitable for 4G Tx/Rx applications such as cellular base stations and remote radio heads where a DSA is required to adjust the power level. In diversity Rx applications, the fast switching PE43204 protects the receive path and prevents overdriving the ADC.

The new PE43204 DSA delivers high linearity over temperature and frequency, and is capable of an 18dB attenuation range in 6dB and 12dB steps. Additionally, taking advantage of Peregrine's HaRP technology, the PE43204 demonstrates no gate lag or phase drift, which delivers fast settling time and an input IP3 > +61dBm at 3GHz. The PE43204 features a typical switching time of 26ns with attenuation accuracy of +0.2dB across a wide operating range of DC—3GHz. This is a four-fold improvement compared to GaAs-based alternatives, which have switching speeds of up to 130nS.

"Leading LTE equipment manufacturers turned to Peregrine to solve their gain control needs for a high linearity, fast switching and settling time DSA which is critical to protecting the receive path in LTE base stations," said Mark Schrepferman, director of communication and industrial products for Peregrine Semiconductor. "Peregrine's new PE43204 DSA leverages the patented UltraCMOS and HaRP technologies to deliver these benefits for reliable and more accurate performance, while also pushing the limits on integration and low power consumption, making it ideal for manufacturers striving to meet the requirements of the LTE specification."

An additional benefit to next-generation communication systems is low current consumption. The PE43204 DSA is biased from a 3V supply with power supply current of 8µA typical. The device also features parallel control interface programming logic and low insertion loss of 0.6 dB typical. As with all UltraCMOS silicon-on-sapphire RFICs, the new DSA offers exceptional low-frequency performance, superior noise immunity and outstanding ESD tolerance of 2kV HBM.

The PE43204, offered in the ultra-compact 12-lead 3mm x 3mm x 0.85mm QFN package, is available now in volume priced at Rs.34.03 ($0.70) for 50K units. Evaluation kits are available to qualified customers.

Environment-friendly tech
UltraCMOS mixed-signal process technology is a patented variation of silicon-on-insulator (SOI) technology on a sapphire substrate providing with high yields and competitive costs. It combines the RF, mixed-signal, and digital capabilities of any other CMOS process, yet tolerates the high power required for high-performance wireless applications. Significant performance advantages exist over competing processes such as GaAs, SiGe, BiCMOS and bulk silicon CMOS in applications where RF performance, low power and integration are paramount. The company's design inventions, such as HaRP technology which enables dramatic improvements in harmonic results, linearity and overall RF performance; and DuNE technology, an advanced digital tuning capability, are paving the way for unprecedented RF IC development. More importantly, UltraCMOS-based RFICs offer an environmentally friendly option to arsenic-based GaAs ICs which have historically been widely used in RF and wireless systems. With the global move towards 'green engineering' and RoHS, UltraCMOS SOS devices are poised to offer engineers and manufacturers alike a simple, responsible solution for the next-generation designs demanded by the environmentally conscious consumer.

- Henri Arnold
EE Times Europe

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