Texas Instruments DAC8801/11EVM, Руководство пользователя

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Jumper Setting
6.4 Output Gain of Five With MDAC V
OUT
Inverted
Table 4 shows the proper jumper settings of the EVM to achieve a gain of five with the output of the
MDAC inverted.
Table 4. Jumper Settings for a Gain of Five With Inverted Output
Jumper Setting
Reference Unipolar Bipolar Function
Output of MDAC is inverted with a gain of 5. Watch for clipping in unipolar mode due to
J5 1-2 and 3-4 1-2 and 3-4
operational amplifier headroom issue.
W15 OPEN OPEN Disconnect the inverting input of operational amplifier, U4A, from AGND.
Supplies power, V
SS
, to the negative rail of operational amplifier, U4A, for bipolar
W5 2-3 1-2
supply mode, or ties it to AGND for unipolar supply mode.
7 Jumper Setting
Table 5 shows the function of each specific jumper setting of the EVM.
Table 5. Jumper Setting Function
Jumper
Reference Setting Function
Routes the –10-V reference to MDAC V
REF
pin.
Disconnect the onboard external reference and use desired source of reference via TP1.
W1
Routes the +10-V reference to MDAC V
REF
pin.
Chip Enable pin driven by CS pin, J2-1.
Enable chip via W25 jumper.
W2
Chip Enable pin driven by FSX pin, J2-7.
Disconnect the I
OUT
from the I-to-V amplifier circuit.
W3
Routes the I
OUT
to the I-to-V amplifier circuit.
Negative supply rail of the output operational amplifier, U4A, is powered by V
SS
for bipolar
operation.
W5
Negative supply rail of the output operational amplifier, U4A, is tied to AGND for unipolar
operation.
11 SLAU151A – January 2005 – Revised November 2009 DAC8801/11EVM
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