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Analog Devices AD9912 User Manual

1 gsps direct digital synthesizer with 14-bit dac, Ad9912, Features

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1 GSPS Direct Digital

Synthesizer with 14-Bit DAC

AD9912

Rev. D

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
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

Fax: 781.461.3113 ©2007–2009 Analog Devices, Inc. All rights reserved.

FEATURES

1 GSPS internal clock speed (up to 400 MHz output directly)
Integrated 1 GSPS 14-bit DAC
48-bit frequency tuning word with 4 µHz resolution
Differential HSTL comparator
Flexible system clock input accepts either crystal or external

reference clock

On-chip low noise PLL REFCLK multiplier
2 SpurKiller channels
Low jitter clock doubler for frequencies up to 750 MHz
Single-ended CMOS comparator; frequencies of <150 MHz
Programmable output divider for CMOS output
Serial I/O control
Excellent dynamic performance
Software controlled power-down
Available in two 64-lead LFCSP packages
Residual phase noise @ 250 MHz

10 Hz offset: −113 dBc/Hz
1 kHz offset: −133 dBc/Hz
100 kHz offset: −153 dBc/Hz
40 MHz offset: −161 dBc/Hz

APPLICATIONS

Agile LO frequency synthesis
Low jitter, fine tune clock generation
Test and measurement equipment
Wireless base stations and controllers
Secure communications
Fast frequency hopping

GENERAL DESCRIPTION

The AD9912 is a direct digital synthesizer (DDS) that features
an integrated 14-bit digital-to-analog converter (DAC). The
AD9912 features a 48-bit frequency tuning word (FTW) that
can synthesize frequencies in step sizes no larger than 4 μHz.
Absolute frequency accuracy can be achieved by adjusting the
DAC system clock.
The AD9912 also features an integrated system clock phase-
locked loop (PLL) that allows for system clock inputs as low
as 25 MHz.
The AD9912 operates over an industrial temperature range,
spanning −40°C to +85°C.

BASIC BLOCK DIAGRAM

FDBK_IN

DAC_OUT

AD9912

S1 TO S4

OUT

OUT_CMOS

FILTER

SYSTEM CLOCK

MULTIPLIER

SERIAL PORT,

I/O LOGIC

CLOCK

OUTPUT

DRIVERS

DIGITAL

INTERFACE

06763-

001

DIRECT

DIGITAL

SYNTHESIS

CORE

STARTUP

CONFIGURATION

LOGIC

Figure 1.

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