GENERAL DESCRIPTION

The AD9874 is a general-purpose IF subsystem that digitizes a low level 10 MHz to 300 MHz IF input with a signal bandwidth ranging from 6.8 kHz to 270 kHz. The signal chain of the AD9874 consists of a low noise amplifier, a mixer, a band-pass sigma-delta analog-to-digital converter, and a decimation filter with programmable decimation factor. An automatic gain control (AGC) circuit gives the AD9874 12 dB of continuous gain adjustment. Auxiliary blocks include both clock and LO synthesizers.

FEATURES

10 MHz to 300 MHz Input Frequency

7.2 kHz to 270 kHz Output Signal Bandwidth

8.1 dB SSB NF

0 dBm IIP3

AGC Free Range up to –34 dBm

12 dB Continuous AGC Range

16 dB Front End Attenuator

Baseband I/Q 16-Bit (or 24-Bit) Serial Digital Output

LO and Sampling Clock Synthesizers

Programmable Decimation Factor, Output Format, AGC, and Synthesizer Settings

370 Ω Input Impedance

2.7 V to 3.6 V Supply Voltage

Low Current Consumption: 20 mA

48-Lead LQFP Package (1.4 mm Thick)

APPLICATIONS

Multimode Narrow-Band Radio Products

Analog/Digital UHF/VHF FDMA Receivers

TETRA, APCO25, GSM/EDGE

Portable and Mobile Radio Products

Base Station Applications

SATCOM Terminals