Filters Guard Handsets From EMI And ESD Effects

Demand is surging for advanced multimedia capabilities in wireless handsets, and that means new design challenges on the electromagnetic-interference (EMI) front. Clamshell phones pose a particularly sticky challenge in terms of avoiding EMI woes. Data rates from the processor to the phones' high-resolution displays have risen dramatically. The result is even more pernicious EMI risks.

Aimed squarely at solving EMI and electrostatic-discharge (ESD) issues, the Praetorian ASIP line of inductor-based filter arrays offers high filtering performance combined with robust ESD protection. The company's Praetorian process technology allows the integration of spiral inductors with resistors, capacitors, and ESD protection diodes in a single-chip format. As a result, the CM1450 and CM1451 filter arrays offer high cutoff frequencies, minimal insertion loss, sharp rolloff, excellent signal integrity, and greater attenuation levels at high frequencies.

Both the CM1450 and CM1451 are based on a five-pole LC filter architecture (15 pf/17 nH/15 pF/17 nH/15 pF and 10 pF/17 nH/10 pF/17 nH/10 pF, respectively) that attenuates signals by 35 db or more over a frequency range of 800 MHz to 2.7 GHz. For the frequency range of 3 to 6 GHz, the attenuation level is greater than 30 dB.

The CM1450 is sampling now. Pricing starts at $0.85 each in lots of 1000 for the six-channel version. The CM1451 also is sampling now. Please call the company for pricing. Production quantities of both devices are scheduled for the second quarter of 2005. Both come in a lead-free CSP package.