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 archi-

tecture reduces system cost compared to devices with

IF-based architectures. The MAX2106 directly tunes L-

band 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 charge-

pump-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 genera-

tor 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).

Applications

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

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 Minimizes Component

Count

o 1MBaud to 45MBaud Operation

o Selectable LO Buffer

o +5V Single-Supply Operation

o 925MHz to 2175MHz Input Frequency Range

o On-Chip Quadrature Generator, Dual-Modulus

Prescaler (/32, /33)

o On-Chip Crystal Oscillator Amplifier

o PLL Phase Detector with Gain-Controlled Charge

Pump

o Input Levels: -25dBm to -68dBm per Carrier

o Over 50dB Gain Control Range

o Noise Figure = 10.2dB; IIP3 = +11.5dBm

(at 1550MHz)

o Automatic Baseband Offset Correction

DBS Direct Downconverter

________________________________________________________________ Maxim Integrated Products

1

19-1627; Rev 2; 6/03

Functional Diagram appears at end of data sheet.

Ordering Information

Pin Configuration

*Exposed paddle.

48 TQFP-EP*

PIN-PACKAGE

TEMP RANGE

0°C to +85°C

MAX2106UCM

PART

PLLIN-

PLLIN+

MOD-

MOD+

LODIVSEL

IOUT+

IOUT-

QOUT+

QOUT-

RFBAND

FLCLK

CFLT

XTL-

XTL+

GND

RFIN-

RFIN+

GND

GND

QDC-

QDC+

1

2

3

4

5

6

7

8

9

10

11

12

36

35

34

33

32

31

30

29

28

27

26

25

TQFP

MAX2106

TOP VIEW

U.S. DSS Set-Top Receivers

European DVB-Compliant

Systems

Cellular Base Stations

Wireless Local Loop

Broadband Systems

LMDS

Professional Receivers

VSAT

Microwave Links

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.