AD5439 Analog Devices, AD5439 Datasheet - Page 16

• Manufacturer Part Number: AD5439
• Description: (AD5424 - AD5547) High Bandwidth Multiplying DACs
• Manufacturer: Analog Devices

AD5547/AD5557
BIPOLAR MODE
4-Quadrant Multiplying Mode, V
The AD5547/AD5557 contain on-chip all the 4-quadrant
resistors necessary for 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 24). For example, with a +10 V reference,
the circuit yields a precision, bipolar –10 V to +10 V output.
Table 9 shows some of the results for the 16-bit AD5547.
V
V
OUT
OUT
= (D/32768 − 1) × V
= (D/16384 − 1) × V
+15V
1µF
C1
+5V
16/14 DATA
C2
0.1µF
A0, A1
LDAC
MSB
WR
0.1µF
REF
REF
RS
4
C3
VIN
GND
(AD5547)
(AD5557)
2
VOUT
ADR01
TRIM
OUT
U3
VDD
WR
= –V
6
5
LDAC
Figure 24. 4-Quadrant Multiplying Mode, V
AD5547/AD5557
R
R1
REF
1A
to +V
RS
R
AD8512
COMA
U2A
MSB A0, A1
REF
U1
C8
R2
V
REFA
(5)
(6)
–10V
Rev. 0 | Page 16 of 20
2
16-/14-BIT
+10V
R
ROFS
OFSA
DAC A
Table 9. AD5547 Output vs. Code
D in Binary
1111 1111 1111 1111
1000 0000 0000 0001
1000 0000 0000 0000
0111 1111 1111 1111
0000 0000 0000 0000
R
RFB
FBA
OUT
= –V
AGNDA
REF
I
OUTA
to +V
REF
C9
U2B
+15V
AD8512
–15V
+V
–V
C5 0.1µF
C6 0.1µF
C4 1µF
C7 1µF
V
+V
+V
0
–V
–V
OUT
REF
REF
REF
REF
(1/32,768)
(32,767/32,768)
(1/32,768)
–10V TO +10V
VOUT