PDF AD8347 Download

Description

The AD8347 is a broadband direct quadrature demodulator with RF and baseband automatic gain control (AGC) amplifiers. It is suitable for use in many communications receivers, performing
quadrature demodulation directly to baseband frequencies. The input frequency range is 800 MHz to 2.7 GHz. The outputs can be connected directly to popular A-to-D converters such as the
AD9201and AD9283. The RF input signal goes through two stages of variable gain amplifiers prior to two Gilbert-cell mixers. The LO quadrature phase splitter employs polyphase filters to achieve high quadrature accuracy and amplitude balance over the entire operating frequency range. Separate I and Q channel variable gain amplifiers follow the baseband outputs of the mixers. The
RF and baseband amplifiers together provide 69.5 dB of gain control. A precision control circuit sets the linear-in-dB RF gain response to the gain control voltage.

Features

1. Integrated RF and baseband AGC amplifiers
2. Quadrature phase accuracy 1° typ
3. I/Q amplitude balance 0.3 dB typ
4. Third-order intercept (IIP3) +11.5 dBm @ min gain
5. Noise figure 11 dB @ max gain
6. AGC range 69.5 dB
7. Baseband level control circuit
8. Low LO drive −8 dBm
9. ADC-compatible I/Q outputs
10. Single supply 2.7 V to 5.5 V
11. Power-down mode

Applications

1. Cellular base stations
2. Radio links
3. Wireless local loop
4. IF broadband demodulators
5. RF instrumentation
6. Satellite modems

For cellular basestations, radio links, wireless local loop, IF broadband demodulator