CM1282 ESD device protects mobile antennas

The CM1282 is based on CMD's Picoguard line of low capacitance ESD protection products, providing high levels of dynamic resistance, clamping voltage and insertion loss.

Low insertion loss is a critical consideration because of the very low power signals received from FM transmitters and GPS satellites.

These performance characteristics and a space efficient, small form factor package make the CM1282 a suitable ESD solution for antenna protection in mobile handsets.

'Feature phones and smart phones that incorporate FM receivers, GPS, Bluetooth and WLAN are expected to grow as a category at a 62 per cent CAGR from 2008 through 2011, a rate 22 times faster than handset market growth for this same period,' said Tina Teng, senior wireless communications analyst for Isuppli Corporation.

In addition to the mobile handset market, location-based services using GPS are also becoming increasingly popular in the latest laptop, PDA and netbook designs.

The internal antennas that are required are highly susceptible to ESD strikes that can damage the handset's internal baseband and application processors.

When selecting ESD protection devices, mobile handset designers need to consider capacitance, standard ESD ratings, and most importantly, clamping voltage and dynamic resistance.

The amount of dynamic resistance determines the amount of residual current and voltage that the device being protected is subjected to during an ESD event.

The lower the dynamic resistance of the ESD protection diode, the greater the portion of the current and voltage that is diverted away from the device being protected.

'Picoguard solutions, including the CM1282, feature low levels of dynamic resistance, residual current and clamping voltages, offering customers effective ESD protection,' said Kyle Baker, vice-president of marketing for California Micro Devices.