General Description

The monolithic MAX2451 is a quadrature demodulator with a supporting oscillator and divide-by-8 prescaler. It operates from a single +3V supply and draws only 5.5mA. The demodulator accepts an amplified and filtered IF signal in the 35MHz to 80MHz range, and demodulates it into I and Q baseband signals with 51dB of voltage conversion gain. The IF input is terminated with a 400Ω thin-film resistor for matching to an external IF filter. The baseband outputs are fully differential and have 1.2Vp-p signal swings.

Features

♦ Integrated Quadrature Phase Shifters

♦ On-Chip Oscillator (Requires External Tuning Circuit)

♦ 51dB Voltage Conversion Gain

♦ On-Chip Divide-by-8 Prescaler

♦ Baseband Output Bandwidth Up to 9MHz

♦ CMOS-Compatible Enable

♦ 5.5mA Operating Supply Current 2µA Shutdown Supply Current

Applications

Digital Cordless Phones

GSM and North American Cellular Phones

Wireless LANs

Digital Communications

Pagers