Evaluation Board User Guide
UG-382
One Technology Way • P.O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Tel: 781.329.4700 • Fax: 781.461.3113 • www.analog.com
Evaluation Board for FSK
AD5700/AD5700-1
HART Modem
FEATURES
Convenient connections for power through screw
Terminal block
Use of on-chip RC oscillator or an external crystal
Various link options
GENERAL DESCRIPTION
This user guide describes the evaluation board for the
AD5700/
AD5700-1
Highway Addressable Remote Transducer (HART®)
modem. This board can be used to evaluate either the
AD5700
or the
AD5700-1
part. Both can operate from a single 1.71 V to
5.5 V supply, with the AD5700-1 having the added feature of
an integrated oscillator.
Complete specifications for both products can be found in the
AD5700/AD5700-1
data sheet available from Analog Devices,
Inc., which should be consulted in conjunction with this user
guide when using the evaluation board.
EQUIPMENT NEEDED
Host controller with UART interface
EVALUATION BOARD
Figure 1.
PLEASE SEE THE LAST PAGE FOR AN IMPORTANT
WARNING AND LEGAL TERMS AND CONDITIONS.
Rev. A | Page 1 of 8
10565-001
UG-382
TABLE OF CONTENTS
Features .............................................................................................. 1
Equipment Needed ........................................................................... 1
General Description ......................................................................... 1
Evaluation Board .............................................................................. 1
Revision History ............................................................................... 2
Evaluation Board Hardware ............................................................ 3
Evaluation Board User Guide
Power Supplies ...............................................................................3
Link Options ..................................................................................3
Evaluation Board Schematics and Artwork ...................................4
Ordering Information .......................................................................7
Bill of Materials ..............................................................................7
REVISION HISTORY
5/13—Rev. 0 to Rev. A
Changed Supply Min from 2 V to 1.71 V ...................................... 1
2/12—Revision 0: Initial Version
Rev. A | Page 2 of 8
Evaluation Board User Guide
EVALUATION BOARD HARDWARE
POWER SUPPLIES
AGND and DGND are connected together on the board to
provide a single GND signal. To power the
EVAL-AD5700-1EBZ,
supply 3.3 V between the V
CC
and GND inputs for the analog
supply of the
AD5700/AD5700-1.
With L5 inserted (default), this
also provides power to IOV
CC
.
Table 1. Default Link Options
Link No.
CLK_CFG1
CLK_CFG0
XTAL_EN
FILTER_SEL
L1
L2
REF_EN
DUPLEX
L5
L6
L8
Option
A
A
A
B
A
A
B
A
Inserted
Not inserted
Inserted
UG-382
LINK OPTIONS
A number of links on the evaluation board must be set for the
required operating setup before using the board. The functions
of these link options are described in detail in Table 2. The
default setup is using the on-chip reference, the crystal
oscillator, and the internal receive filter (see Table 1).
Table 2. Link Functions
Link No.
CLK_CFG1,
CLK_CFG0,
XTAL_EN
FILTER_SEL, L1, L2
REF_EN
DUPLEX
L5
L6
L8
Function
The
AD5700/AD5700-1
support numerous clocking configurations to allow a simple, low cost solution. The
AD5700/AD5700-1
can use an external crystal or ceramic resonator, a CMOS input, or an internal RC oscillator
(AD5700-1 only). The CLK_CFG0, CLK_CFG1, and XTAL_EN links configure the clock generation as follows:
XTAL_EN
CLK_CFG1
CLK_CFG0 CLKOUT
Description
B
A
A
No output
3.6864 MHz CMOS clock connected at XTAL1 pin
B
A
B
No output
1.2288 MHz CMOS clock connected at XTAL1 pin
B
B
A
No output
Internal oscillator enabled
B
B
B
1.2288 MHz output
Internal oscillator enabled, CLKOUT enabled
A
A
A
No output
Crystal oscillator enabled
A
A
B
3.6864 MHz output
Crystal oscillator enabled, CLKOUT enabled
A
B
A
1.8432 MHz output
Crystal oscillator enabled, CLKOUT enabled
A
B
B
1.2288 MHz output
Crystal oscillator enabled, CLKOUT enabled
These link options set whether the internal or external receive band-pass filter is used at the HART input.
Setting FILTER_SEL to Position B and L1 and L2 to Position A sets the board to use the internal receive band-pass filter.
Setting FILTER_SEL to Position A and L1 and L2 to Position B sets the board to use the external receive band-pass filter.
This sets whether the internal or an external reference is used.
Position A—disables the internal reference, and a buffered external 2.5 V reference source must be applied at REF.
Position B—enables the internal 1.5 V reference and buffer.
Allows the modulator and demodulator of the
AD5700/AD5700-1
to be enabled at the same time.
Position A—the
AD5700/AD5700-1
operate in half-duplex operation (controlled by RTS).
Position B—the
AD5700/AD5700-1
operate in full duplex operation, with the modulator and demodulator of the
AD5700/AD5700-1 enabled at the same time.
Allows V
CC
to be connected directly to IOV
CC
.
Inserted—V
CC
is connected to IOV
CC
.
Not inserted—V
CC
is disconnected from IOV
CC
.
Do not insert this link.
This link must be inserted.
Rev. A | Page 3 of 8