AD9287 Analog Devices, AD9287 Datasheet - Page 35

• Manufacturer Part Number: AD9287
• Description: Quad, 8-Bit, 100 MSPS Serial LVDS 1.8 V A/D Converter
• Manufacturer: Analog Devices

Specifications of AD9287

• Resolution (bits): 8bit
• # Chan: 4
• Sample Rate: 100MSPS
• Interface: LVDS,Ser
• Analog Input Type: Diff-Uni
• Ain Range: 2 V p-p
• Adc Architecture: Pipelined
• Pkg Type: CSP

Data Sheet
EVALUATION BOARD
The AD9287 evaluation board provides all of the support cir-
cuitry required to operate the ADC in its various modes and
configurations. The converter can be driven differentially using a
transformer (default) or an AD8332 driver. The ADC can also be
driven in a single-ended fashion. Separate power pins are provided
to isolate the DUT from the drive circuitry of the AD8332. Each
input configuration can be selected by changing the connection
of various jumpers (see Figure 62 to Figure 66). Figure 60 shows
the typical bench characterization setup used to evaluate the ac
performance of the AD9287. It is critical that the signal sources
used for the analog input and clock have very low phase noise
(<1 ps rms jitter) to realize the optimum performance of the
converter. Proper filtering of the analog input signal to remove
harmonics and lower the integrated or broadband noise at the
input is also necessary to achieve the specified noise performance.
See Figure 62 to Figure 70 for the complete schematics and
layout diagrams demonstrating the routing and grounding
techniques that should be applied at the system level.
POWER SUPPLIES
This evaluation board has a wall-mountable switching power
supply that provides a 6 V, 2 A maximum output. Connect the
supply to the rated 100 V ac to 240 V ac wall outlet at 47 Hz to
63 Hz. The other end of the supply is a 2.1 mm inner diameter
jack that connects to the PCB at P503. Once on the PC board,
the 6 V supply is fused and conditioned before connecting to
three low dropout linear regulators that supply the proper bias
to each of the various sections on the board.
When operating the evaluation board in a nondefault condition,
L504 to L507 can be removed to disconnect the switching
power supply. This enables the user to bias each section of the
WALL OUTLET
100V TO 240V AC
47Hz TO 63Hz
ROHDE & SCHWARZ,
ROHDE & SCHWARZ,
2V p-p SIGNAL
SYNTHESIZER
2V p-p SIGNAL
SYNTHESIZER
SMHU,
SMHU,
SWITCHING
SUPPLY
POWER
BAND-PASS
FILTER
2A MAX
6V DC
XFMR
INPUT
CLK
–
5.0V
EVALUATION BOARD
+
AD9287
–
1.8V
+
Figure 60. Evaluation Board Connection
–
1.8V
+
Rev. E | Page 35 of 52
–
CH A TO CH D
3.3V
+
SERIAL
LVDS
8-BIT
SPI
board individually. Use P501 to connect a different supply for
each section. At least one 1.8 V supply is needed for AVDD_DUT
and DRVDD_DUT; however, it is recommended that separate
supplies be used for analog and digital signals and that each supply
have a current capability of 1 A. To operate the evaluation board
using the VGA option, a separate 5.0 V analog supply (AVDD_5 V)
is needed. To operate the evaluation board using the SPI and alter-
nate clock options, a separate 3.3 V analog supply (AVDD_3.3 V)
is needed in addition to the other supplies.
INPUT SIGNALS
When connecting the clock and analog sources to the evaluation
board, use clean signal generators with low phase noise, such as
Rohde & Schwarz SMHU or HP8644 signal generators or the
equivalent, as well as a 1 m, shielded, RG-58, 50 Ω coaxial cable.
Enter the desired frequency and amplitude from the ADC specifi-
cations tables. Typically, most Analog Devices evaluation boards
can accept approximately 2.8 V p-p or 13 dBm sine wave input
for the clock. When connecting the analog input source, it is
recommended to use a multipole, narrow-band, band-pass filter
with 50 Ω terminations. Good choices of such band-pass filters
are available from TTE, Allen Avionics, and K&L Microwave, Inc.
The filter should be connected directly to the evaluation board
if possible.
OUTPUT SIGNALS
The default setup uses the Analog Devices HSC-ADC-FIFO5-
INTZ to interface with the Analog Devices standard dual-channel
FIFO data capture board (HCS-ADC-EVALCZ). Two of the
eight channels can be evaluated at the same time. For more
information on the channel settings and optional settings of
these boards, visit www.analog.com/FIFO.
INTERPOSER
BOARD
SPI
HSC-ADC-EVALCZ
FIFO DATA
CAPTURE
BOARD
–
CONNECTION
3.3V
SPI
+
USB
SPI
SOFTWARE
ANALYZER
RUNNING
AD9287
AND SPI
USER
ADC
PC