ANALOG DEVICES UG-285 Service Manual

Evaluation Board User Guide

UG-285

AD5544

V

OUT

A

V

OUT

D

SDINSCLKCS

SDO

LDAC

RS
MSB

I

OUT

D

USB

EVAL-SDP-CB1Z

GPIO

SPORT

V

REF

x

I

OUT

A

ADR01

REFERENCE

AD8065

I-TO-V

AD8065

I-TO-V

09900-001

One Technology Way • P. O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Tel: [phone] • Fax: [phone] • www.analog.com

Evaluating the AD5544 Current Output/Serial Input DAC

FEATURES

Full-featured evaluation board for the AD5544
Graphic user interface software for board control and data

analysis

Connector to E VAL-SDP-CB1Z system demonstration

platform board

Various power supply options

APPLICATIONS

Automatic test equipment
Instrumentation
Digitally controlled calibration

GENERAL DESCRIPTION

The AD5544 quad, 16-bit, current output, digital-to-analog
converter (DAC) is designed to operate in a 2.7 V to 5.5 V
supply range. But this voltage is limited up to 3.3 V due to
EVAL-SDP-CB1Z restrictions.

The applied external reference input voltage (V
the full-scale output current. Integrated feedback resistors
(R

x) provide temperature-tracking, full-scale voltage outputs

FB

when combined with an external I-to-V precision amplifier.

x) determines

REF

A double-buffered serial data interface offers high speed, 3-wire,
SPI- and microcontroller-compatible inputs using serial data in
(SDI), chip select (
serial data out pin (SDO) allows for daisy-chaining when
multiple packages are used. A common, level-sensitive, load
DAC strobe (
all DAC outputs from previously loaded input registers.
Additionally, an internal power-on reset forces the output
voltage to 0 at system turn on. An MSB pin allows system reset
assertion (

RS

or to half-scale code when MSB = 1.

The AD5544 is packaged in a compact 28-lead SSOP.

The E VA L -AD5544/45SDZ board is used in conjunction with
the EVA L -SDP-CB1Z system demonstration platform (SDP)
board available from Analog Devices, Inc., which is purchased
separately from the evaluation board. The USB-to-SPI
communication to the AD5544 is completed using this
Blackfin®-based demonstration board. The software offers a
waveform generator.

CS

), and clock (CLK) signals. In addition, a

LDAC

) input allows the simultaneous update of

) to force all registers to zero code when MSB = 0

PLEASE SEE THE LAST PAGE FOR AN IMPORTANT
WARNING AND LEGAL TERMS AND CONDITIONS.

FUNCTIONAL BLOCK DIAGRAM

Figure 1.

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UG-285 Evaluation Board User Guide

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications ....................................................................................... 1

General Description ......................................................................... 1

Functional Block Diagram .............................................................. 1

Revision History ............................................................................... 2

Evaluation Board Software .............................................................. 3

Installing the Software ................................................................. 3

REVISION HISTORY

5/12—Rev. 0 to Rev. A

Changes to General Description Section ...................................... 1

Changes to Figure 2 .......................................................................... 3

Changes to Evaluation Board Schematics and Artwork Section ... 5

5/11—Revision 0: Initial Versi on

Running the Software ...................................................................3

Using the Evaluation Board Software .............................................4

Example ..........................................................................................4

Evaluation Board Schematics and Artwork ...................................5

Evaluation Board Layout ..............................................................8

Related Links ......................................................................................9

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Evaluation Board User Guide UG-285

09900-002

09900-003

EVALUATION BOARD SOFTWARE

Figure 2. Device Manager Showing the SDP Board Connected

INSTALLING THE SOFTWARE

The EVAL-AD5544/45SDZ evaluation kit includes the software
and drivers on CD. To install the software, do the following:

1. Install the software before connecting the SDP board to the

USB port of the PC.

2. Start the Windows® operating system and insert the EVAL-

AD5544/45SDZ evaluation kit CD.

3. Download the E VA L -AD5544/45SDZ LabVIEW™ software.

The correct driver, SDPDriversNET, for the SDP board
should download automatically after LabVIEW is
downloaded, supporting both 32- and 64-bit systems.
However, if the drivers do not download automatically, the
driver executable file can also be found in the Program
Files/Analog Devices folder. Follow the on-screen prompts
to install it.

4. After installation of the software and drivers is complete, plug

the EVA L -AD5544/45SDZ into the SDP board and the SDP
board into the PC using the USB cable included in the box.

5. When the software detects the evaluation board, proceed

through any dialog boxes that appear to finalize the
installation (Found New Hardware Wizard/Install the
Software Automatically and so on).

RUNNING THE SOFTWARE

To run the evaluation board program, do the following:

1. Click Start/All Programs/Analog Devices/EVAL-

AD5544/45SDZ.

2. If the SDP board is not connected to the USB port when

the software is launched, a connectivity error displays (see
Figure 3). Simply connect the evaluation board to the USB
port of the PC, wait a few seconds, click Rescan, and follow
the instructions.

Figure 3.

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UG-285 Evaluation Board User Guide

09900-004

09900-005

V

D

VV

REF

OUT

5.2

536,65

384,16

10

536,65

−=×−=×−=

V

D

VV

REF

OUT

5.7

536,65

152,49

10

536,65

−=×−=×−=

USING THE EVALUATION BOARD SOFTWARE

Once the software is launched, the main window pops up (see
Figure 4).

The desired 16-bit data loads and updates one of the four DACs
that you selected within the AD5544 part.

There are two modes for loading the data. Synchronous mode
enables you to program each channel separately and update
them simultaneously. Program

LDAC

and finally pull

low. Asynch-ronous mode enables you

to load and update each channel separately (the

LDAC

high, load the channels,

LDAC

button

is ignored in this case).

RS

The reset button,

, updates all channel outputs to zero scale

or midscale when MSB is pulled low or high.

EXAMPLE

LDAC

With
specify quarter scale (0x4000, 16384d) in the Input Data box
and click Load and Update DAC A. The expected output
obtained is

and RS tied high for asynchronous loading mode,

Figure 4. Main Window

The first step is to select the device to use that is connected
to the SDP board, in this case the AD5544, and click OK.

After selecting the device, the AD5544 evaluation software
window appears (see Figure 5) to start writing to the device.

When you change the loading synchronism mode to synch­ronous and write the value 0xC000 (49152d), you see no change
in the output until

LDAC

is tied low. The expected output for

this case is

Figure 5. AD5544 Evaluation Software Window

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