AD7944
Rev. A | Page 9 of 28
TYPICAL PERFORMANCE CHARACTERISTICS
AVDD = DVDD = VIO = 2.5 V, BVDD = 5.0 V, VREF = 5.0 V, external reference (PDREF is high, REFIN is low), unless otherwise noted.
0
4096
8192
12,288
16,384
–1.0
–0.8
–0.6
–0.4
–0.2
0
0.2
0.4
0.6
0.8
1.0
CODE
IN
L
(L
SB
)
04658-
105
POSITIVE INL = +0.12 LSB
NEGATIVE INL = –0.20 LSB
Figure 5. Integral Nonlinearity vs. Code
04658-
106
0
2
4899
149
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
8188
8189
8190
8191
8192
8193
8194
8195
8196
CO
UNT
CODE IN HEX
126,022
Figure 6. Histogram of DC Input at Code Center (External Reference)
04658-
110
0
2
5236
1438
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
8188
8189
8190
8191
8192
8193
8194
8195
8196
CO
UNT
CODE IN HEX
124,396
Figure 7. Histogram of DC Input at Code Center (Internal Reference)
0
4096
8192
12,288
16,384
–1.0
–0.8
–0.6
–0.4
–0.2
0
0.2
0.4
0.6
0.8
1.0
CODE
DN
L
(L
SB
)
04658-
108
POSITIVE DNL = +0.11LSB
NEGATIVE DNL = –0.11LSB
Figure 8. Differential Nonlinearity vs. Code
04658-
109
0
324
62,982
0
10,000
20,000
30,000
40,000
50,000
60,000
80,000
70,000
8188
8189
8190
8191
8192
8193
8194
8195
CO
UNT
CODE IN HEX
67,766
Figure 9. Histogram of DC Input at Code Transition (External Reference)
04658-
107
0
7
63,238
2
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
8189
8190
8191
8192
8193
8194
8195
8196
CO
UNT
CODE IN HEX
67,825
Figure 10. Histogram of DC Input at Code Transition (Internal Reference)