DAC16 Analog Devices, DAC16 Datasheet - Page 5

• Manufacturer Part Number: DAC16
• Description: 16-Bit High Speed Current-Output DAC
• Manufacturer: Analog Devices

REV. B
Digital Input Considerations
The threshold of the DAC16’s digital input circuitry is set at
1.4 V, independent of supply voltage. Hence, the digital inputs
can interface with any type of 5 V logic. Illustrated in Figure 5 is
the equivalent circuit of the digital inputs. Note that the indi-
vidual input capacitance is approximately 7 pF.
Figure 7. Integral Nonlinearity vs. I
Figure 5. Equivalent Circuit of a DAC16 Digital Input
–10
–15
–1
–2
–3
–4
15
10
–5
4
3
2
1
0
5
0
0.2
Figure 10. Gain Error vs.
Temperature
–40
DBX
REFERENCE CURRENT – mA
0.3
–20
TEMPERATURE – C
0
0.4
Q1
R1
20k
+INL
–INL
20
0.5
40
–15V
V
V
I
V
V
T
Q2
REF
CC
EE
A
CC
EE
60
= +25 C
= +5V
= –15V
+5V
= –15V
= 0.5mA
= +5V
0.6
R2
75k
80
–0.7V
Q3
R3
28k
0.7
REF
+0.7V
TO DAC
SWITCH
Figure 8. Differential Nonlinearity
vs. I
Figure 11. Integral Nonlinearity
vs. Temperature
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
–2
–4
0
4
2
0
0.2
REF
–40
Typical Performance Characteristics–DAC16
0.3
REFERENCE CURRENT – mA
–20
TEMPERATURE – C
–5–
0
0.4
+DNL
+INL
–DNL
–INL
20
This input capacitance can be used in conjunction with an ex-
ternal R-C circuit for digital signal deskewing, if required. In
applications where some of the DAC16’s digital inputs are
not used, the recommended procedure to turn off one or more
inputs is to connect each input line to +5 V as shown in
Figure 6.
0.5
V
V
I
40
Figure 6. Handling Unused DAC16 Digital Inputs
REF
CC
EE
V
V
T
CC
EE
A
= –15V
= +5V
= 0.5mA
60
= +25 C
= +5V
= –15V
0.6
80
0.7
+5V
Figure 12. Differential Nonlinearity
vs. Temperature
–0.5
–1.0
–1.5
Figure 9. Zero Scale Output vs.
Temperature
1.5
1.0
0.5
1.0
0.8
0.6
0.4
0.2
0
0
–40
–40
DB0
DB1
DAC16
–20
–20
TEMPERATURE – C
TEMPERATURE – C
0
0
+DNL
–DNL
20
20
40
V
V
I
40
REF
CC
EE
V
V
I
REF
CC
EE
= –15V
= +5V
= 0.5mA
60
60
= –15V
= +5V
= 0.5mA
80
80