a
FEATURES
200 MHz Internal Clock Rate
14-Bit Data Path
Excellent Dynamic Performance
80 dB SFDR @ 65 MHz ( 100 kHz) A
OUT
4 –20 Programmable Reference Clock Multiplier
Reference Clock Multiplier PLL Lock Detect Indicator
Internal 32-Bit Quadrature DDS
FSK Capability
8-Bit Output Amplitude Control
Single-Pin Power-Down Function
Four Programmable, Pin-Selectable Signal “Profiles”
SIN(x)/x Correction (Inverse SINC Function)
Simplified Control Interface
10 MHz Serial, 2- or 3-Wire SPI-Compatible
3.3 V Single Supply
Single-Ended or Differential Input Reference Clock
80-Lead LQFP Surface-Mount Packaging
Three Modes of Operation
Quadrature Modulator Mode
Single-Tone Mode
Interpolating DAC Mode
CMOS 200 MSPS 14-Bit
Quadrature Digital Upconverter
AD9857
APPLICATIONS
HFC Data, Telephony, and Video Modems
Wireless Base Station
Agile, L.O. Frequency Synthesis
Broadband Communications
GENERAL DESCRIPTION
The AD9857 integrates a high-speed direct-digital synthesizer
(DDS), a high-performance, high-speed 14-bit digital-to-analog
converter (DAC), clock multiplier circuitry, digital filters, and other
DSP functions onto a single chip, to form a complete quadrature
digital upconverter device. The AD9857 is intended to function as
a universal I/Q modulator and agile upconverter, single-tone DDS,
or interpolating DAC for communications applications, where
cost, size, power dissipation, and dynamic performance are critical
attributes.
The AD9857 offers enhanced performance over the industry-
standard AD9856, as well as providing additional features.
The AD9857 is available in a space-saving surface-mount
package and is specified to operate over the extended industrial
temperature range of –40°C to +85°C.
FUNCTIONAL BLOCK DIAGRAM
INVERSE
CIC FILTER
FIXED
INTER-
POLATOR
M
U
X
I
PARALLEL
DATA IN
(14-BIT)
D 14
E
M 14
U
X
Q
PROGRAMMABLE
INTERPOLATOR
CIC
(2 – 63 )
M
U
X
QUADRATURE
MODULATOR
AD9857
INVERSE
SINC FILTER
M 14
U
X
8
DAC CLOCK
DAC_RSET
IOUT
IOUT
INV
CIC
(4 )
M
U
X
COS
SIN
INV
SINC
14-BIT
DAC
INVERSE CIC CONTROL
INVERSE CIC CLOCK
HALF-BAND CLOCKS
INTERP CONTROL
INTERP CLOCK
DATA CLOCK
INVERSE
SINC CLOCK
DDS
CORE
CLOCK
OUTPUT
SCALE
VALUE
TUNING
WORD
32
CONTROL REGISTERS
TIMING & CONTROL
SYNCH
SYSCLK
POWER-
DOWN
LOGIC
PROFILE
SELECT
LOGIC
M
U
X
CLOCK
MULTIPLIER
(4 – 20 )
MODE
CONTROL
REFCLK
REFCLK
CIC
PDCLK/ TxENABLE RESET
OVERFLOW
FUD
SERIAL
PORT
DIGITAL
POWER-
DOWN
PS1 PS0
PLL
LOCK
CLOCK
INPUT
MODE
REV. 0
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2000
AD [ ANALOG DEVICES ]
