MAX2106

19-1627; Rev 2; 6/03 DBS Direct Downconverter General Description The MAX2106 low-cost, direct-conversion tuner IC is designed for use in digital direct-broadcast satellite (DBS) television set-top box units and is a pin-for-pin upgrade for the MAX2104. Its direct-conversion architecture reduces system cost compared to devices with IF-based architectures. The MAX2106 directly tunes Lband signals to baseband using a broadband I/Q downconverter. The operating frequency range spans 925MHz to 2175MHz. The IC includes a low-noise amplifier (LNA) with gain control, I and Q downconverting mixers, lowpass filters with gain and frequency control, a local oscillator (LO) buffer with a 90° quadrature network, and a chargepump-based phase-locked loop (PLL) for frequency control. The MAX2106 has an on-chip LO, requiring only an external varactor-tuned LC tank for operation. The LO’s output drives the internal quadrature generator and has a buffer amplifier to drive off-chip circuitry. The MAX2106 comes in a 48-pin thin quad flat-pack package with exposed paddle (EP). Advantages Over MAX2104 o Improved Front End Achieves 10.2dB NF at 1550MHz o Higher Input IIP3: 11.5dBm at 1550MHz o Reduced Spurious Downconversion Products o Capable of Using an External Synthesizer MAX2106 Features o Drop-In Replacement for MAX2104 Designs: Requires Only Minor Software Upgrade and Two External Resistor Value Changes o Complete Low-Cost Solution for DBS Direct Downconversion o High Level of Integration ...