The AD608 series Low Power Mixer/Limiter/RSSI Receiver IF Subsystem uses a successive-detection technique. In addition, the AD608 provides both a high speed received signal strength indicator (RSSI) output with 80dB dynamic range and a hard-limited output. The RSSI output is from a two-pole post demodulation low-pass filter and provides a loadable output voltage of 0.2 to 1.8V. The AD608 operates from a single 2.7 to 5.5V supply at a typical power level of 21mW at 3V. The RF and local oscillator (LO) bandwidths both exceed 500MHz. In a typical IF application, the AD608 can accept the output of a 240MHz surface acoustic wave (SAW) filter and down-convert it to a nominal 10.7MHz IF with a conversion gain of 24dB (ZIF = 165R). The AD608 logarithmic/limiting amplifier section handles any IF from low frequency (LF) up to 30MHz. The mixer is a doubly balanced gilbert-cell mixer and operates linearly for RF inputs spanning -95 to -15dBm. It has a nominal -5dBm third-order intercept.
● 15dBm, 1dB Compression point, 5dBm IP3 (Mixer)
● 24dB Conversion gain (Mixer)
● >500MHz Input bandwidth (Mixer)
● 80dB RSSI range (Logarithmic/limiting amplifier)
● ±3° phase Stability over 80dB range (Logarithmic/limiting amplifier)
● Low power
● 21mW at 3V power consumption
● CMOS-compatible power-down to 300µW typical
● 200ns enable/disable time
