GENERAL DESCRIPTION

The AD8319 is a demodulating logarithmic amplifier, capable of accurately converting an RF input signal to a corresponding decibel-scaled output. It employs the progressive compression technique over a cascaded amplifier chain, each stage of which is equipped with a detector cell. The device can be used in either measurement or controller modes. The AD8319 maintains accurate log conformance for signals of 1 MHz to 8 GHz and provides useful operation to 10 GHz. The input dynamic range is typically 45 dB (re: 50 Ω) with error less than ±3 dB. The AD8319 has 6 ns/10 ns (fall time/rise time) response time that enables RF burst detection to a pulse rate of beyond 50 MHz. The device provides unprecedented logarithmic intercept stability vs. ambient temperature conditions. A supply of 3.0 V to 5.5 V is required to power the device. Current consumption is typically 22 mA, and it decreases to 200 µA when the device is disabled.

FEATURES

Wide bandwidth: 1 MHz to 10 GHz

High accuracy: ±1.0 dB over temperature

45 dB dynamic range up to 8 GHz

Stability over temperature: ±0.5 dB

Low noise measurement/controller output VOUT

Pulse response time (fall/rise): 6 ns/10 ns

Small footprint: 2 mm × 3 mm LFCSP

Supply operation: 3.0 V to 5.5 V @ 22 mA

Fabricated using high speed SiGe process

APPLICATIONS

RF transmitter PA setpoint controls and level monitoring

Power monitoring in radiolink transmitters

RSSI measurement in base stations, WLANs, WiMAX,

and radars