AD9957/PCBZ Analog Devices Inc, AD9957/PCBZ Datasheet - Page 20

• Manufacturer Part Number: AD9957/PCBZ
• Description: D/A Converter Evaluation Board
• Manufacturer: Analog Devices Inc
• Series: AgileRF™r

Specifications of AD9957/PCBZ

• Silicon Manufacturer: Analog Devices
• Application Sub Type: Direct Digital Synthesizer
• Kit Application Type: Clock & Timing
• Silicon Core Number: AD9957
• Kit Contents: Board
• Main Purpose: Timing: DDS Modulators
• Embedded: No
• Utilized Ic / Part: AD9957
• Primary Attributes: 14-Bit DAC, 32-Bit Tuning Word Width
• Secondary Attributes: 1GHz, Graphical User Interface
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AD9957
SINGLE TONE MODE
A block diagram of the AD9957 operating in single tone mode
is shown in Figure 29; grayed items are inactive. In this mode,
both I and Q data paths are disabled from the 18-bit parallel
data port up to, and including, the modulator. The internal
DDS core produces a single frequency signal based on the
programmed tuning word. The user may select either the
TxENABLE
PDCLK
I/Q IN
FTW
10
PW
TIMING AND CONTROL
PROGRAMMING
PARALLEL DATA
REGISTERS
3
18
16
18
16
QS
Q
IS
I
SERIAL I/O
PORT
INTERNAL CLOCK TIMING AND CONTROL
I Q
RAM
Figure 29. Single Tone Mode
IS QS
Rev. B | Page 20 of 64
OSK
AD9957
cos (ωt+θ)
θ
ω
sin (ωt+θ)
CLOCK
CONTROL
DDS
POWER
DOWN
cosine or sine output of the DDS. The sinusoid at the DDS
output can be scaled using a 14-bit amplitude scale factor (ASF)
and optionally routed through the inverse sinc filter.
Single tone mode offers the output shift keying (OSK) function.
It provides the ability to ramp the amplitude scale factor between
zero and an arbitrary preset value over a programmable time
interval.
2
2
SYSCLK
DAC GAIN
PLL
÷2
8
OUTPUT
FACTOR
SCALE
8-BIT
AUX
DAC
14-BIT
DAC
DAC_RSET
IOUT
IOUT
REFCLK_OUT
REF_CLK
REF_CLK
XTAL_SEL