UG-1042 Datasheet, PDF (3/24 Pages) Analog Devices – Fully featured evaluation board for 10-lead precision

Easy to Use AD4000 Series16-/18-Bit Precision SAR ADCs User Guide
UG-1042
EVALUATION BOARD HARDWARE
(OPTIONAL)
–V_S
GND
+V_S
POWER SUPPLY CIRCUITRY
ADP7118, ADP7104, ADP2370, ADM660, ADP7182
+7V/+5V/–2.5 +1.8V
+7V +3.3V
(OPTIONAL)
VDD
GND
VSDP
12V
ADR4550
5V
VCM
ADA4807-1
ADA4807-1
12V
WALL WART
12V
USB PORT
POWER
SUPPLY
CIRCUITRY
VIN+
VIN–
ADA4807-1 ^+7V
–2.5V
+7V
ADA4807-1
–2.5V
AB
VDD REF VIO
IN+ _AD4000/ SDI
AD4001/ ^SCK
AD4003 SDO
IN–
GND ^CNV
SPI
INTERFACE
ADSP-BF527
SPARTAN-6
FPGA
XC6SLX25
EASY TO USE AD4000 SERIES 16-BIT/18-BIT
PRECISION SAR ADCs EVALUATION BOARD
EVAL-SDP-CH1Z
120-PIN
CONNECTOR
Figure 2. Simplified Evaluation Board Block Diagram
SETTING UP THE EVALUATION BOARD
Figure 2 shows the simplified evaluation board block diagram.
Figure 25 shows the evaluation board schematic. The board
consists of the ADC, U1, with a reference, U6 (ADR4550), and
ADC drivers, U12 and U14, the ADA4807-1 for the AD4003/
AD4001 and the ADA4805-1 for the AD4000 (see Table 5).
The user also has an option to use a low power, fully differential
ADC driver, U2, by populating the ADA4940-1. The evaluation
board is a flexible design that enables the user to select
components in addition to operating from an adjustable bench
top power supply.
POWER SUPPLIES
The system demonstration platform (SDP-H1) board supplies
12 V to power necessary rails for the AD4000/AD4001/AD4003
evaluation board.
Table 1. Power Supplies Provided on the Board
Power Supply (V) Function
Components Used
5, 7 (default)¹
Positive rail
−5, −2.5 (default)¹ Negative rail
ADP7118
ADP2370, ADM660,
ADP7182
1.8
ADC power
ADP7118, ADP5300
3.3
VDRIVE (digital power) ADP7118
1 _{See Table 2.}
The 7 V amplifier positive rail (+VS) is generated from U17,
(the ADP7118). The −2.5 V negative amplifier rail (−VS) is
generated by a combination of U3 (the ADP2370), U7 (the
ADM660), and U21 (the ADP7182).
Each supply is decoupled where it enters the board and again at
each device. A single ground plane is used on this board to
minimize the effect of high frequency noise interference.
In addition to this, there is also the ability to power the board
from a bench top power supply. The screw terminals, J2 and J3, are
provided for this function. When bench power is used, the on-
board power supplies are no longer required. Solder links also
must be changed: SL1 = SL2 = SL5 = SL6 = SL7 = SL8 = SL9 = B.
REFERENCE, REFERENCE BUFFER, AND COMMON-
MODE BUFFER
An external 5 V reference (U6, ADR4550) is used by default to
supply the ADCs directly. However, the user can also use one of
the 2.5 V, 3.3 V, and 4.096 V references by changing the reference
(U6) on the board. There is also an option to use a lower power
reference (U22, ADR3450). Note that the ADR3450 cannot
accept input voltage beyond 5.5 V. The ADA4807-1 is used as a
reference buffer (U16) and common-mode buffer (U18) by
default. However, it can also be replaced by the AD8031 if
needed without compromising the performance.
SDP-H1 CONTROLLER BOARD
The evaluation board uses the SPI interface and it is connected
to the high speed controller board for the system demonstration
platform (SDP-H1) controller board. The SDP-H1 board requires
power from a 12 V wall adapter. The SDP-H1 has a Xilinx®
Spartan 6 and an ADSP-BF527 processor with connectivity to the
PC through a USB 2.0 high speed port. Controller boards allow
the configuration and capture of data on daughter boards from
the PC via USB.
Rev. B | Page 3 of 24