DAC701 Datasheet, PDF (9/12 Pages) Burr-Brown (TI) – Monolithic 16-Bit DIGITAL-TO-ANALOG CONVERTERS

VOLTAGE OUTPUT MODELS
ANALOG OUTPUT
DAC701 UNIPOLAR
DIGITAL INPUT CODE
16-BIT
15-BIT
14-BIT
16-BIT
1LSB
0000_H
FFFF_H
(µV)
153
(V)
+9.99985
(V)
0
305
+9.99969
0
610
+9.99939
0
ANALOG OUTPUT MODEL
305
+9.99960
–10.0000
ANALOG OUTPUT
DAC702 BIPOLAR
DIGITAL INPUT CODE
16-BIT
15-BIT
1LSB
0000_H
FFFF_H
(µA)
(mA)
(mA)
0.031
–0.99997
+1.00000
0.061
–0.99994
+1.00000
TABLE II. Digital Input and Analog Output Relationships.
DAC703 BIPOLAR
15-BIT
610
+9.99939
–10.0000
14-BIT
1224
+9.99878
–10.0000
14-BIT
0.122
–0.99988
+1.00000
If the output cannot be sensed at Common or the system
ground point as mentioned above, the differential output
circuit shown in Figure 8 is recommended. In this circuit the
output voltage is sensed at the load common and not at the
D/A converter common as in the previous circuits. The value
of R₆ and R₇ must be adjusted for maximum common-mode
rejection at R_L. Note that if R₃ is negligible, the circuit of
Figure 8 can be reduced to the one shown in Figure 7. Again
the effect of R₄ is negligible.
The D/A converter and the wiring to its connectors should be
located to provide optimum isolation from sources of RFI
and EMI. The key concept in elimination of RF radiation or
pickup is loop area; therefore, signal leads and their return
conductors should be kept close together. This reduces the
external magnetic field along with any radiation. Also, if a
single lead and its return conductor are wired close together,
they present a small flux-capture cross section for any
external field. This reduces radiation pickup in the circuit.
DAC702
R_F
R₁
R_F *
R_DAC *
I_OUT
A₁
Common _{RB ‡}
R₂
R_L
R₃
Alternate Ground
Sense Connection
To +V_CC
1µF
1µF
To –V_CC
To V_DD
1µF
R₄
Sense Output
+V
COM
–V
System Ground
Point
+V
±15VDC
Supply
COM
+5VDC
Supply
*
R_B
R_F
R_DAC
DAC702 2.45kΩ
10k Ω
2.45k Ω
‡ _{RB should be equal to the output impedance at the current output}
to compensate for the bias current drift of A₁. Use standard 10%,
1/4W carbon composition or equivalent resistors.
FIGURE 7. Preferred External Op Amp Configuration.
DAC702
R_F
R₁
R_F *
I_OUT
R_DAC *
Common
R₆
A₁
R₇
R₂
R_L
R₅
Alternate Ground
Sense Connection
R₄
R₃
To +V_CC
To –V_CC
To V_DD
+V
1µF
COM ±15VDC
1µF
Supply
–V
System Ground
Point
+V
1µF
COM +5VDC
Supply
Sense
Output
DAC702
R_F
10k Ω
R_DAC
2.45k Ω
R₅ + R₇ = R_F + R₁
R₆ = R_DAC
FIGURE 8. Differential Sensing Output Op Amp
Configuration.
®
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DAC701, 702, 703