50 MHz to 2200 MHz

Quadrature Modulator

ADL5385

Rev. 0

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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other

rights of third parties that may result from its use. Specifications subject to change without notice. No

license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

Trademarks and registered trademarks are the property of their respective owners.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781.329.4700 www.analog.com

FEATURES

Output frequency range: 50 MHz to 2200 MHz

1 dB output compression: 11 dBm @ 350 MHz

Noise floor: –159 dBm/Hz @ 350 MHz

Sideband suppression: −50 dBc @ 350 MHz

Carrier feedthrough: −46 dBm @ 350 MHz

Single supply: 4.75 V to 5.5 V

24-lead, Pb-free LFCSP_VQ with exposed paddle

APPLICATIONS

Radio-link infrastructure

Cable modem termination systems

Wireless infrastructure systems

Wireless local loop

WiMAX/broadband wireless access systems

FUNCTIONAL BLOCK DIAGRAM

TEMPERATURE

SENSOR

BIAS

VOUT

TEMP

ENBL

IBBP

IBBN

QBBP

QBBN

LOIP

LOIN

DIVIDE-BY-2

QUADRATURE

PHASE

SPLITTER

6118-001

Figure 1.

PRODUCT DESCRIPTION

The ADL5385 is a silicon, monolithic, quadrature modulator

designed for use from 50 MHz to 2200 MHz. Its excellent phase

accuracy and amplitude balance enable both high performance

intermediate frequency (IF) and direct radio frequency (RF)

modulation for communication systems.

The AD5385 takes the signals from two differential baseband

inputs and modulates them onto two carriers in quadrature

with each other. The two internal carriers are derived from

a single-ended, external local oscillator input signal at twice the

frequency as the desired carrier output. The two modulated

signals are summed together in a differential-to-single-ended

amplifier designed to drive 50 Ω loads.

The ADL5385 can be used as either an IF or a direct-to-RF

modulator in digital communication systems. The wide

baseband input bandwidth allows for either baseband drive or

drive from a complex IF. Typical applications are in radio-link

transmitters, cable modem termination systems, and broadband

wireless access systems.

The ADL5385 is fabricated using the Analog Devices, Inc.,

advanced silicon germanium bipolar process and is packaged in

a 24-lead, Pb-free LFCSP_VQ with exposed paddle.

Performance is specified over –40°C to +85°C. A Pb-free

evaluation board is also available.

ADL5385

Rev. 0 | Page 2 of 24

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications....................................................................................... 1

Functional Block Diagram .............................................................. 1

Product Description......................................................................... 1

Specifications..................................................................................... 3

Absolute Maximum Ratings............................................................ 6

ESD Caution.................................................................................. 6

Pin Configuration and Functional Descriptions.......................... 7

Typical Performance Characteristics ............................................. 8

Circuit Description......................................................................... 12

Overview...................................................................................... 12

LO Interface................................................................................. 12

V-to-I Converter......................................................................... 12

Mixers .......................................................................................... 12

D-to-S Amplifier......................................................................... 12

Bias Circuit.................................................................................. 12

Basic Connections .......................................................................... 13

Optimization............................................................................... 13

Applications..................................................................................... 15

DAC Modulator Interfacing ..................................................... 15

155 Mbps (STM-1) 128 QAM Transmitter............................. 16

CMTS Transmitter Application................................................ 16

Spectral Products from Harmonic Mixing............................. 17

RF Second-Order Products....................................................... 17

LO Generation Using PLLs ....................................................... 18

Transmit DAC Options ............................................................. 18

Modulator/Demodulator Options ........................................... 18

Evaluation Board ............................................................................ 19

Characterization Setup .................................................................. 21

SSB Setup..................................................................................... 21

Outline Dimensions ....................................................................... 22

Ordering Guide .......................................................................... 22

REVISION HISTORY

10/06—Revision 0: Initial Version

ADL5385

Rev. 0 | Page 3 of 24

SPECIFICATIONS

Unless otherwise noted, V

= 5 V; T

= 25°C; LO = −7 dBm; I/Q inputs = 1.4 V p-p differential sine waves in quadrature on a 500 mV dc

bias; baseband frequency = 1 MHz; LO source and RF output load impedances are 50 Ω.

Table 1.

Parameter Conditions Min Typ Max Unit

OUTPUT FREQUENCY RANGE 50 2200 MHz

EXTERNAL LO FREQUENCY

RANGE

External LO frequency is twice output frequency 100 4400 MHz

OUTPUT FREQUENCY = 50 MHz

Output Power Single (lower) sideband output 4 5.6 8 dBm

Output P1 dB 11 dBm

Carrier Feedthrough Unadjusted (nominal drive level) −57 dBm

@ +85°C after optimization at +25°C −67 dBm

@ −40°C after optimization at +25°C −67 dBm

Sideband Suppression Unadjusted (nominal drive level) −57 dBc

@ +85°C after optimization at +25°C −64 dBc

@ −40°C after optimization at +25°C −68 dBc

Second Baseband Harmonic (F

− (2 × F

)), P

OUT

= 5 dBm −83 dBc

Third Baseband Harmonic (F

+ (3 × F

)), P

OUT

= 5 dBm −58 dBc

Output IP2 F1 = +3.5 MHz, F2 = +4.5 MHz, P

OUT

= −3 dBm per tone 69 dBm

Output IP3 F1 = +3.5 MHz, F2 = +4.5 MHz, P

OUT

= −3 dBm per tone 26 dBm

Quadrature Phase Error −0.17 degrees

I/Q Amplitude Balance −0.03 dB

Noise Floor 20 MHz offset from LO, all BB inputs at a bias of 500 mV −155 dBm/Hz

20 MHz offset from LO, output power = −5 dBm −150 dBm/Hz

Output Return Loss −19 dB

OUTPUT FREQUENCY = 140 MHz

Output Power Single (lower) sideband output 5.7 dBm

Output P1 dB 11 dBm

Carrier Feedthrough Unadjusted (nominal drive level) −52 dBm

@ +85°C after optimization at +25°C −66 dBm

@ −40°C after optimization at +25°C −67 dBm

Sideband Suppression Unadjusted (nominal drive level) −53 dBc

@ +85°C after optimization at +25°C −63 dBc

@ −40°C after optimization at +25°C −68 dBc

Second Baseband Harmonic (F

− (2 × F

)), P

OUT

= 5 dBm −83 dBc

Third Baseband Harmonic (F

+ (3 × F

)), P

OUT

= 5 dBm −57 dBc

Output IP2 F1 = +3.5 MHz, F2 = +4.5 MHz, P

OUT

= −3 dBm per tone 70 dBm

Output IP3 F1 = +3.5 MHz, F2 = +4.5 MHz, P

OUT

=−3 dBm per tone 26 dBm

Quadrature Phase Error −0.33 degrees

I/Q Amplitude Balance −0.03 dB

Noise Floor 20 MHz offset from LO, all BB inputs at a bias of 500 mV −160 dBm/Hz

Output Return Loss −20 dB

OUTPUT FREQUENCY = 350 MHz

Output Power Single (lower) sideband output 3 5.6 7 dBm

Output P1 dB 11 dBm

Carrier Feedthrough Unadjusted (nominal drive level) −46 dBm

@ +85°C after optimization at +25°C −65 dBm

@ −40°C after optimization at +25°C −66 dBm

Sideband Suppression Unadjusted (nominal drive level) −50 dBc

@ +85°C after optimization at +25°C −63 dBc

@ −40°C after optimization at+25°C −61 dBc

Part #	ADL5385ACPZ
Description
Category	IC
Availability	In Stock
Qty	5

Qty	Price
1 - 1	$8.88561
2 - 2	$7.06810
3 - 3	$6.66420
4 +	$6.19300

ADL5385ACPZ

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