Datasheet

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REV O
EVAL-AD9831EB
Link and Switch Options
There are five link options which must be set for the required operating setup before using the evaluation board. The functions
of these options are outlined below.
Link No. Function
LK1 The PSEL1 input can be controlled by the user via a BNC connector or, alternatively, by switch SW.
When LK1 is arranged so that PSEL1 is connected to SW, the user can control the PSEL1 signal using the
double throw switch.
Alternatively, PSEL1 can be tied to a BNC connector by altering LK1 so that the user can provide the PSEL1
control from a logic source.
LK2 The PSEL0 input can be controlled by the user via a BNC connector or, alternatively, by switch SW.
When LK2 is arranged so that PSEL0 is connected to SW, the user can control the PSEL0 signal using the
double throw switch.
Alternatively, PSEL0 can be tied to a BNC connector by altering LK2 so that the user can provide the PSEL0
control from a logic source.
LK3 The FSELECT input can be controlled by the user via a BNC connector or, alternatively, by switch SW.
When LK3 is arranged so that FSELECT is connected to SW, the user can control the FSELECT signal using
the double throw switch.
Alternatively, FSELECT can be tied to a BNC connector by altering LK3 so that the user can provide the
FSELECT control from a logic source.
LK4 LK4 is used to place the AD9831 in sleep mode.
When LK4 is connected so that
SLEEP is tied to DGND, the AD9831 is placed in sleep mode whereby the
AD9831's internal clocks, REFOUT and the DAC are disabled.
When LK4 is connected so that
SLEEP is tied to DVDD, the AD9831 is powered up.
LK5 The reference to the AD9831 can be provided by the on-board reference, which is available at REFOUT, or an
external reference of nominal value 1.21 V can be used. When LK5 is closed, the on-board reference is used.
When this link is opened, REFIN is disconnected from REFOUT and the reference can be provided by the
user via a BNC connector.