Dual-Purpose Log Amp Measures And Controls RF Signals From 1 MHz To 10 GHz

Applications include wireless infrastructure, broadband wireless, and radar

Norwood, MA -- Analog Devices, Inc. (ADI) today announced the industry's first RF logarithmic detector/controller that accurately measures the power of radio signals from 1 MHz to 10 GHz, covering all cellular standards and a variety of wireless infrastructure and broadband wireless applications. In addition, the device offers fast output response time (enabling RF burst detection in radar applications), a tiny 2 mm by 3 mm package for space-constrained applications, and low-power consumption for portable applications. These features, packed into one small IC (integrated circuit), allow manufacturers to reduce inventory and leverage design costs by having one device that can be used in several products.

Accurate power measurement and control are critical to improving system performance and ensuring regulatory compliance. The AD8317 demodulating log amp (logarithmic amplifier) offers accurate RF measurement of better than +/- 1 dB over a dynamic range of more than 50 dB, and can function as a power controller when its outputs are used to adjust a PA (power amplifier) or a VGA (variable-gain amplifier), such as ADI's ADL5330. The wide 1 MHz to 10 GHz operating frequency range supports all cellular standards (GSM, CDMA, W-CDMA, and TD-SCDMA), broadband wireless standards (802.16, WiMAX, WiBro), and proprietary systems that operate in a variety of frequency bands.

The AD8317 provides precise, temperature-stable performance over the full range of -40 to +85 degrees C, and an output response time of 5 nanoseconds, enabling RF burst detection to beyond 125 MHz. The device operates over a supply voltage range of 3 to 5 V, consuming only 20 mA of current; power consumption is reduced to less than 1 mW when the device is disabled.

The AD8317 is sampling now, with volume production scheduled for October 2005.

Source: Analog Devices