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Optimum Technology Matching® Applied

GaAs HBT

InGaP HBT

GaAs MESFET

SiGe BiCMOS

Si BiCMOS

SiGe HBT

GaAs pHEMT

Si CMOS

Si BJT

GaN HEMT

Functional Block Diagram

RF MICRO DEVICES®, RFMD®, Optimum Technology Matching®, Enabling Wireless Connectivity™, PowerStar®, POLARIS™ TOTAL RADIO™ and UltimateBlue™ are trademarks of RFMD, LLC. BLUETOOTH is a trade-

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Product Description

7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical

support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.

RF MEMS

LDMOS



Synth

Phase

det.

Ref.

divider

RFMD2081

45MHz TO 2700MHz IQ MODULATOR

WITH SYNTHESIZER/VCO

The RFMD2081 is a low power, wideband, IQ modulator with integrated fractional-N synthesizer

and voltage controlled oscillator (VCO). The modulator features an input 3dB bandwidth of

100MHz, and can generate output frequencies of between 45MHz and 2700MHz, making it

suitable for a wide range of applications.

The fractional-N synthesizer takes advantage of an advanced sigma-delta architecture that

delivers ultra-fine step sizes and low spurious products. The synthesizer/VCO, combined with

an external loop filter, allows the user to generate local oscillator (LO) signals from 90MHz to

5400MHz. The LO signal is buffered and routed to a high accuracy quadrature divider (/2) that

drives the balanced I and Q mixers. The output of the mixers are summed and applied to a dif-

ferential RF output stage. This device also features a differential input for an external VCO or LO

source.

Device programming is achieved via a simple 3-wire serial interface. In addition, a unique pro-

gramming mode allows up to four devices to be controlled from a common serial bus. This elim-

inates the need for separate chip-select control lines between each device and the host

controller. Up to six general purpose outputs are provided, which can be used to access internal

signals (the LOCK signal, for example) or to control front end components. The device is opti-

mized for low power operation, consuming typically only 135mA from a 3V supply.

Features



RF Output Frequency Range

45MHz to 2700MHz



Fractional-N Synthesizer with

Very Low Spurious Levels



Typical Step Size 1.5Hz



Fully Integrated Wideband VCOs

and LO Buffers



Integrated Phase Noise

<0.2° rms at 1GHz



-40dBc Unadjusted Carrier

Suppression



-40dBc Unadjusted Sideband

Suppression



100MHz Baseband Input 3dB

Bandwidth



Very Low Noise Floor

-162dBm/Hz Typical



Output P1dB + 4dBm



Output IP3 + 17dBm



2.7V to 3.3V Power Supply



135mA Typical Current

Consumption



Serial Programming Interface

Applications



Satellite Communications



QPSK/QAM Modulators



Wireless Broadband



Point-to-Point



Software Defined Radios

DS140110

Package: QFN, 32-Pin, 5mm x 5mm

RFMD2081