Datasheet

Data Sheet AD5546/AD5556
Rev. D | Page 13 of 20
03810-024
V
DD
R
OFS
R
OFSA
VOUT
R
FB
R
FBA
C6
GND
U1
AD5546/AD5556
I
OUT
R2
R1
R
COMA
R1A
16-/14-BIT
DATA
16-/14-BIT
D
ATA
VREFA
U2B
OP2177
–
+
C4
1µF
C5
0.1µF
C8
1µF
C9
0.1µF
+15V
–15V
WR
WR
LDAC
LDAC
RS
RS
MSB
MSB
C2
0.1µF
C1
1µF
V+
V–
U2A
OP2177
+
–
C7
+5V
+10V
–10V
Figure 20. Unipolar Two-Quadrant Multiplying Mode, V
OUT
= 0 to +V
REF
2
5V
6
5
4
GND
V
IN
TRIM
U3
ADR03
V
OUT
5V V
DD
R1
R
OFS
R
OFS
–VREF TO +VREF
VOUT
R
FB
R
FB
C2
GND
U1
AD5546/AD5556
I
OUT
R2
U2A
OP2177
+
–
C1
–VREF +VREF
R
COM
R1
16-/14-BIT
DATA
16-/14-BIT
DATA
REF
U2B
OP2177
–
+
WR
WR
LDAC
LDAC
RS
RS
MSB
MSB
03810-002
Figure 21. Four-Quadrant Multiplying Mode, V
OUT
= –V
REF
to +V
REF
BIPOLAR MODE
Four-Quadrant Multiplying Mode, V
OUT
= –V
REF
to +V
REF
The AD5546/AD5556 contain on-chip all the four-quadrant
resistors necessary for the precision bipolar multiplying
operation. Such a feature minimizes the number of exponent
components to only a voltage reference, dual op amp, and
compensation capacitor (see Figure 21). For example, with a
10 V reference, the circuit yields a precision, bipolar –10 V to
+10 V output.
AD5546
V
OUT
= (D/32768 − 1) × V
REF
(5)
AD5556
V
OUT
= (D/16384 − 1) × V
REF
(6)
Table 10 shows some of the results for the 16-bit AD5546.