Analog Devices UG-397 User manual

Evaluation Board User Guide
UG-397
One Technology Way •P. O. Box 9106 •Norwood, MA 02062-9106, U.S.A. •Tel: [phone] •Fax: [phone] •www.analog.com
Evaluation Board for the AD5247 Digital Potentiometer
PLEASE SEE THE LAST PAGE FOR AN IMPORTANT
WARNING AND LEGAL TERMS AND CONDITIONS.Rev. 0 | Page 1 of 16
FEATURES
Full-featured board in conjunction with low voltage digiPOT
motherboard (EVAL-MB-LV-SDZ)
Various test circuits
Various ac/dc input signals
PC control via a separately purchased system demonstration
platform (SDP-B or SDP-S)
PC software for control
PACKAGE CONTENTS
EVAL-AD5247DBZ
EVAL-MB-LV-SDZ motherboard
CD that includes
Self-installing software that allows users to control the
board and exercise all functions of the device
Electronic version of the AD5247 data sheet
Electronic version of the UG-397 user guide
GENERAL DESCRIPTION
This user guide describes the evaluation board for evaluating the
AD5247, a single channel, 128-position digital potentiometer.
The AD5247 supports a single-supply 2.7 V to 5.5 V operation,
making the device suited for battery-powered applications and
many other applications with a superior low temperature
coefficient performance.
In addition, the AD5247 uses a versatile I2C serial interface that
operates in fast mode, allowing speeds of up to 400 kHz.
The E VA L -AD5247DBZ and E VA L -MB-LV-SDZ can operate in
single-supply mode and incorporate an internal power supply
from the USB.
Complete specifications for the AD5247 part can be found in
the AD5247 data sheet, which is available from Analog Devices,
Inc., and should be consulted in conjunction with this user
guide when using the evaluation board.
EVAL-AD5247DBZ WITH MOTHERBOARD AND SDP-B
10625-001
Figure 1. Digital Picture of Evaluation Board with Low Voltage digiPOT Motherboard and System Demonstration Platform

UG-397 Evaluation Board User Guide
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TABLE OF CONTENTS
Features .............................................................................................. 1
Package Contents .............................................................................. 1
General Description ......................................................................... 1
E VA L-AD5247DBZ With Motherboard and SDP-B ................... 1
Revision History ............................................................................... 2
Evaluation Board Hardware ............................................................ 3
Power Supplies .............................................................................. 3
Link Options ................................................................................. 3
Test Circuits................................................................................... 4
Evaluation Board Software...............................................................6
Installing the Software ..................................................................6
Running the Software ...................................................................6
Software Operation .......................................................................7
Schematics and Artwork ..................................................................8
Motherboard ..................................................................................8
Daughter Board .......................................................................... 12
Ordering Information.................................................................... 15
Bill of Materials........................................................................... 15
REVISION HISTORY
5/12—Revision 0: Initial Version

Evaluation Board User Guide UG-397
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EVALUATION BOARD HARDWARE
POWER SUPPLIES
The EVA L -MB-LV-SDZ supports using single power supplies.
The evaluation board can be powered either from the SDP port
or externally by the J1 and J2 connectors as described in Table 1.
All supplies are decoupled to ground using 10 µF tantalum and
0.1 µF ceramic capacitors.
Table 1. Maximum and Minimum Voltages of the Connectors
Connector No. Label Voltage
J1-1
EXT VDD
Analog positive power supply, V
DD
;
from 2.7 V to 5.5 V.
J1-2 GND Analog ground.
J2-1 VLOGIC Digital supply, from 2.7 V to VDD.
J2-2 DGND Digital ground.
LINK OPTIONS
Several link and switch options are incorporated in the EVAL-
MB-LV-SDZ evaluation board and should be set up before
using the board. Table 2 describes the positions of the links to
control the evaluation board by a PC, via the SDP board. The
functions of these link options are described in detail in Table 3
through Table 6.
Table 2. Link Options Setup for SDP Control (Default)
Link No. Option
A11 3.3 V
A12 AGND
A5 3.3 V
Table 3. Link Functions
Link No.
Power Supply
Options
A11 VDD This link selects one of the following as the positive power supply:
5 V (from SDP).
3.3 V (from SDP).
VDD (external supply from the J1 connector).
A5 VLOGIC This link selects one of the following as the digital supply:
3.3 V (from SDP).
VLOGIC EXT (external supply from the J2 connector).
A12 GND AGND.

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TEST CIRCUITS
The EVAL-AD5247DBZ and EVAL-MB-LV-SDZ incorporate
several test circuits to evaluate the AD5247 performance.
DAC
RDAC can be operated as a digital-to-analog converter (DAC),
as shown in Figure 2.
VOUT1
R34
RDAC
AC+
A
B
W
BUF-W1
+
–
A1
B1
W1
V
DD
– V
SS
V
DD
VDD
2
10625-002
Figure 2. DAC
Table 4 shows the options available for the voltage references.
Table 4. DAC Voltage References
Terminal
Link
(DB1)
Link
(MB2) Options Description
A1 A2-B A9 AC+
Connects Terminal
A1 to VDD /2
VDD
Connects Terminal
A1 to VDD
W1 A3-B
BUF-
W1
Connects Terminal
W1 to an output
buffer
B1 A10 AGND
A1
inserted
1Daughter board
2Motherboard
The output voltage is defined in Equation 1.
128
)( RDAC VV A
OUT  (1)
where:
RDAC is the code loaded in the RDAC register.
VAis the voltage applied to the A terminal (A9 link).
However, by using the R34 external resistor, the user can reduce
the voltage of the voltage references. In this case, use the A1 test
point to measure the voltage applied to the A terminal and
recalculate VAin Equation 1.
AC Signal Attenuation
RDAC can be used to attenuate an ac signal, which must be
provided externally using the AC_INPUT connector, as shown
in Figure 3.
VOUT1
R34
RDAC
AC+
AC
A
B
W
BUF-W1
+
–
A
C_INPUT
A1
B1
W1
V
DD
–
V
SS
2
HPF
1kHz
10625-003
Figure 3. AC Signal Attenuator
Depending on the voltage supply rails and the dc offset voltage
of the ac signal, various configurations can be used as described
in Table 5.
Table 5. AC Signal Attenuation Link Options
Link Options Conditions
A9 AC+ No dc offset voltage.
AC signal is outside the voltage supply rails
due to the dc offset voltage.
DC offset voltage ≠ VDD/2.
AC All other conditions.
A10 AGND All other conditions.
The signal attenuation is defined in Equation 2.









 ENDTOEND
WWB
R
RR
nAttenuatio log20)dB( (2)
where:
RWB is the resistor between the W and ground.
RWis the wiper resistance.
REND-TO-END is the end-to-end resistance value.

Evaluation Board User Guide UG-397
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Signal Amplifier
RDAC can be operated as a noninverting signal amplifier
supporting pseudo logarithmic gain. Table 6 shows the available
configurations.
The noninverting amplifier with pseudologarithmic gain is
shown in Table 6, and the gain is defined in Equation 4.
WB
AW
R
R
G1 (4)
where:
RAW is the resistor between the W and A terminals.
RWB is the resistor between the W and B terminals.
VOUT2
VIN
RDAC
A
B
W
+
–
W2
A2 B2
C1
10nF
R41
1.7kΩ
R42
10625-004
Figure 4. Pseudologarithmic Noninverting Amplifier
R42 can be used to set the maximum and minimum gain limits.
Table 6. Amplifier Selection Link Options
Amplifier Gain Link(DB1) Link (MB2) Label VIN Range
Noninverting Pseudo logarithmic A2 = A3 = A4-A A7 LOC 0 V to VDD
A6 N-INV
A1 not inserted A8 N-INV
1Daughter board
2Motherboard

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EVALUATION BOARD SOFTWARE
INSTALLING THE SOFTWARE
The E VA L -AD5247DBZ evaluation kit includes evaluation
board software provided on a CD. The software is compatible
with Windows® XP, Windows Vista, and Windows 7 (both
32 bits and 64 bits).
Install the software before connecting the SDP board to the USB
port of the PC to ensure that the SDP board is recognized
when it is connected to the PC. To install the software, use
the following steps:
1. Start the Windows operating system and insert the CD.
2. The installation software opens automatically. If it does
not, run the setup.exe file from the CD.
3. After installation is completed, power up the evaluation
board as described in the Power Supplies section.
4. Connect the E VA L -AD5247DBZ and EVA L-MB-LV-SDZ
into the SDP board and the SDP board into the PC using
the USB cable included in the evaluation kit.
5. When the software detects the evaluation board, follow the
instructions that appear to finalize the installation.
RUNNING THE SOFTWARE
To run the program, use the following steps:
1. Click Start > All Programs > Analog Devices > AD5247
>AD5247 Eval Board. To uninstall the program, click
Start > Control Panel > Add or Remove Programs >
AD5247 Eval Board.
2. If the SDP board is not connected to the USB port when
the software is launched, a connectivity error displays (see
Figure 5). Simply connect the evaluation board to the USB
port of the PC, wait a few seconds, click Rescan, and follow
the instructions.
10625-005
Figure 5. Pop-Up Window Error
The main window of the E VA L -AD5247DBZ evaluation
software then opens, as shown in Figure 6.
10625-006
Figure 6. EVAL-AD5247DBZ Evaluation Board Software Main Window

Evaluation Board User Guide UG-397
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SOFTWARE OPERATION
The main window of the E VA L -AD5247DBZ software is divided
into the following sections: RDAC and MANUAL DATA.
RDAC
WRITE can be used to update the RDAC registers by entering a
desirable value into the text box and clicking WRITE. When
WRITE is clicked, a write/read operation is performed, and the
value displayed in this section is updated with the actual RDAC
register value. This function can be used to verify whether the
write operation was completed successfully.
MANUAL WRITE
SEND DATA is a customized I2C data-word can be sent by
manually switching the scroll bars from 0 to 1 or from 1 to 0
as desired and then clicking SEND DATA.
In addition, the scroll bars are updated on each write transfer,
showing the command sent to the part.
EXIT closes the program.

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SCHEMATICS AND ARTWORK
MOTHERBOARD
10625-007
Figure 7. SDP Connector and Power Supply

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10625-008
Figure 8. Schematic of Test Circuits

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10625-009
Figure 9. Schematic of Connectors to Daughter Board
10625-010
Figure 10. Component Side View

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10625-011
Figure 11. Component Placement Drawing
10625-012
Figure 12. Layer 2 Side PCB Drawing

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DAUGHTER BOARD
10625-013
Figure 13. Schematic of Daughter Board

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10625-014
Figure 14. Component Side View
10625-015
Figure 15. Component Placement Drawing

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10625-016
Figure 16. Layer 2 Side PCB Drawing

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ORDERING INFORMATION
BILL OF MATERIALS
Table 7. Motherboard
Qty Reference Designator Description Supplier1/Part Number
3 BUF-3, BUF-4, BUF-W1 2-pin (0.1" pitch) header and shorting shunt FEC 1022247 and FEC 150-411
3 A6, A7, A8 3-pin SIL header and shorting link FEC 1022248 and FEC 150410
5 A5, A9, A10, A11, A12 6-pin (3 × 2) 0.1" header and shorting block FEC 148-535 and FEC 150-411
(36-pin strip)
1 J1 3-pin terminal block (5 mm pitch) FEC 151790
2 J7, J8 4-pin SIL header FEC 1098035
1 J4 Receptacle, 0.6 mm, 120-way Digi-Key H1219-ND
1 J10 8-pin inline header; 100 mil centers FEC 1098038
1 J5 12pin (2 × 6) 0.1" pitch header FEC 1098051
2 J2, J3 2-pin terminal block (5 mm pitch) FEC 151789
17 R1, R3, R6, R7, R8, R9, R10, R11,
R12, R13, R20, R22, R23, R34,
R35, R42, R43
SMD resistor 0 Ω, 0.01, 0603 FEC 9331662
1 R2 SMD resistor 2.2 kΩ, 0.01, 0603 FEC 1750676
1 R41 SMD resistor 1.7 kΩ, 1% ,0603 FEC 1170811
1 R21 Resistor, surge, 1.6 Ω, 1%, 0603 FEC 1627674
1 R38 SMD resistor, 2.7 kΩ, 1%, 0603 FEC 1750678
1 R14 SMD resistor 100 Ω, 1%, 0603 FEC 9330364
1 R4 SMD resistor 1 kΩ, 0.01, 0603 FEC 9330380
3 R5, R25, R26 SMD resistor 100 kΩ, 1%, 0603 FEC 9330402
5
R15, R16, R17, R18, R19
SMD resistor 33 kΩ, 1%, 0603
FEC 9331034
1 C1 SMD capacitor, 100 nF, 10%, 0805 FEC 165-0863
8 C4, C9, C10, C11, C12, C17, C19, C21 SMD capacitor, 0.1 µF, ±10%, 0603 FEC 1759122
4 C2, C6, C7, C14 SMD capacitor, 0.1 µF, ±10%, 0603 FEC 301-9482
2 C8, C13 SMD capacitor,10 µF, ±10% FEC 197-130
4 C18, C20, C22, C5 Capacitor 10 µF, ±20% FEC 1190107
2 C3, C15 Capacitor 470 nF, ±10%,0603 FEC 1414037
1 C16 Capacitor 4.7 nF, ±10%,0603 FEC 1414642
1 C34 Capacitor 4.7 nF, ±20% FEC 1432350
1 L2 Inductor, SMD, 600Z FEC 9526862
1 D1 Green SMD LED FEC 5790852
1 U1 2 port level translating bus switch ADG3247BCPZ
1 U2 Dual op amp AD8652ARZ
1 U3 Precision low dropout voltage regulator ADP3303ARZ-3.3
1 U4 Operational amplifier AD8618ARZ
1 U5 I2C serial EEPROM 64K 2.5 V MSOP-8 FEC 1331335
18 /LRDAC, /RESET, /SYNC, /WP, A1,
A2, A3, A4, AGND, B1, VOUT_C1,
VOUT_C2, VOUT3, VOUT4, W1, W2,
W3, W4
Terminal, PCB, black, PK100, test point FEC 8731128
5 +3V3, +5V, VDD, VLOGIC, VSS Terminal, PCB, red, PK100 FEC 8731144
1FEC refers to Farnell Electronic Component Distributors; Digi-Key refers to Digi-Key Corporation.

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Table 8. Daughter Board
Qty Reference Designator Description Supplier1/Part Number
1 U1 256 position digital potentiometer AD5246BKSZ10-RL7/ AD5247BKSZ10-RL7
1 A1 2-pin (0.1" pitch) header and shorting shunt FEC 1022247 and FEC 150-411
2 A2, A3 3-pin SIL header and shorting link FEC 1022248 and FEC 150410
1 C6 6.3 V tantalum capacitor (Case A) 10 μF, ±20% FEC 1190107
1 C3 50 V X7R ceramic capacitor 0.1 μF, ±10%, 0603 FEC 1759122
1 J1 header, 2.54 mm, PCB, 1 × 8 way FEC 1766172
1 J2 12-pin (2 × 6) 0.1" pitch header FEC 1804099
2 J3, J4 5-pin SIL header FEC 1929016
1FEC refers to Farnell Electronic Component Distributors; Digi-Key refers to Digi-Key Corporation.
I2C refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors).
ESD Caution
ESD (electrostatic discharge) sensitive device. Charged devices and circuit boards can discharge without detection. Although this product features patented or proprietary protection
circuitry, damage may occur on devices subjected to high energy ESD. Therefore, proper ESD precautions should be taken to avoid performance degradation or loss of functionality.
Legal Terms and Conditions
By using the evaluation board discussed herein (together with any tools, components documentation or support materials, the “Evaluation Board”), you are agreeing to be bound by the terms and conditions
set forth below (“Agreement”) unless you have purchased the Evaluation Board, in which case the Analog Devices Standard Terms and Conditions of Sale shall govern. Do not use the Evaluation Board until you
have read and agreed to the Agreement. Your use of the Evaluation Board shall signify your acceptance of the Agreement. This Agreement is made by and between you (“Customer”) and Analog Devices, Inc.
(“ADI”), with its principal place of business at One Technology Way, Norwood, MA 02062, USA. Subject to the terms and conditions of the Agreement, ADI hereby grants to Customer a free, limited, personal,
temporary, non-exclusive, non-sublicensable, non-transferable license to use the Evaluation Board FOR EVALUATION PURPOSES ONLY. Customer understands and agrees that the Evaluation Board is provided
for the sole and exclusive purpose referenced above, and agrees not to use the Evaluation Board for any other purpose. Furthermore, the license granted is expressly made subject to the following additional
limitations: Customer shall not (i) rent, lease, display, sell, transfer, assign, sublicense, or distribute the Evaluation Board; and (ii) permit any Third Party to access the Evaluation Board. As used herein, the term
“Third Party” includes any entity other than ADI, Customer, their employees, affiliates and in-house consultants. The Evaluation Board is NOT sold to Customer; all rights not expressly granted herein, including
ownership of the Evaluation Board, are reserved by ADI. CONFIDENTIALITY. This Agreement and the Evaluation Board shall all be considered the confidential and proprietary information of ADI. Customer may
not disclose or transfer any portion of the Evaluation Board to any other party for any reason. Upon discontinuation of use of the Evaluation Board or termination of this Agreement, Customer agrees to
promptly return the Evaluation Board to ADI. ADDITIONAL RESTRICTIONS. Customer may not disassemble, decompile or reverse engineer chips on the Evaluation Board. Customer shall inform ADI of any
occurred damages or any modifications or alterations it makes to the Evaluation Board, including but not limited to soldering or any other activity that affects the material content of the Evaluation Board.
Modifications to the Evaluation Board must comply with applicable law, including but not limited to the RoHS Directive. TERMINATION. ADI may terminate this Agreement at any time upon giving written notice
to Customer. Customer agrees to return to ADI the Evaluation Board at that time. LIMITATION OF LIABILITY. THE EVALUATION BOARD PROVIDED HEREUNDER IS PROVIDED “AS IS” AND ADI MAKES NO
WARRANTIES OR REPRESENTATIONS OF ANY KIND WITH RESPECT TO IT. ADI SPECIFICALLY DISCLAIMS ANY REPRESENTATIONS, ENDORSEMENTS, GUARANTEES, OR WARRANTIES, EXPRESS OR IMPLIED, RELATED
TO THE EVALUATION BOARD INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, TITLE, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT OF INTELLECTUAL
PROPERTY RIGHTS. IN NO EVENT WILL ADI AND ITS LICENSORS BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES RESULTING FROM CUSTOMER’S POSSESSION OR USE OF
THE EVALUATION BOARD, INCLUDING BUT NOT LIMITED TO LOST PROFITS, DELAY COSTS, LABOR COSTS OR LOSS OF GOODWILL. ADI’S TOTAL LIABILITY FROM ANY AND ALL CAUSES SHALL BE LIMITED TOTHE
AMOUNT OF ONE HUNDRED US DOLLARS ($100.00). EXPORT. Customer agrees that it will not directly or indirectly export the Evaluation Board to another country, and that it will comply with all applicable
United States federal laws and regulations relating to exports. GOVERNING LAW. This Agreement shall be governed by and construed in accordance with the substantive laws of the Commonwealth of
Massachusetts (excluding conflict of law rules). Any legal action regarding this Agreement will be heard in the state or federal courts having jurisdiction in Suffolk County, Massachusetts, and Customer hereby
submits to the personal jurisdiction and venue of such courts. The United Nations Convention on Contracts for the International Sale of Goods shall not apply to this Agreement and is expressly disclaimed.
©2012 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
UG10625-0-5/12(0)