Anadigics Inc. has been granted patent 6,580,321 for an active clamping circuit that protects GSM power amplifiers (PAs) from damage under extreme operating conditions. The new clamping circuit is simpler than previous designs and takes up less board real estate, says the developer.

"This active clamping circuit is simple and compact yet protects PAs by reducing the gain of the amplifier when output voltage becomes too high," said Charles Huang, executive vice president and chief technical officer at Anadigics.

The company has an about 30 patents. Some of the resulting products include quad-band GSM PAs and a family of HELP (high-efficiency-at-low-power) CDMA PAs. The recently launched HELP CDMA PAs reduce handset power consumption by 50 percent, delivering an efficiency of 20 percent at +16 dBm as compared with 8 percent to 10 percent for currently available products in the market, according to Anadigics.