CED1Z AD [Analog Devices], CED1Z Datasheet - Page 30

• Manufacturer Part Number: CED1Z
• Description: 8-/6-/4-Channel DAS with 16-Bit,Bipolar Input,Simultaneous Sampling ADC
• Manufacturer: AD [Analog Devices]

AD7606/AD7606-6/AD7606-4
Figure 49 to Figure 55 illustrate the effect of oversampling on
the code spread in a dc histogram plot. As the oversample rate
is increased, the spread of the codes is reduced.
1000
1400
1200
1000
1400
1200
1000
900
800
700
600
500
400
300
200
100
800
600
400
200
800
600
400
200
Figure 50. Histogram of Codes—OS × 2 (Four Codes)
Figure 51. Histogram of Codes—OS × 4 (Four Codes)
Figure 49. Histogram of Codes—No OS (Six Codes)
0
0
0
NO OVERSAMPLING
F
AV
V
OVERSAMPLING BY 2
F
AV
V
OVERSAMPLING BY 4
F
AV
V
SAMPLE
SAMPLE
DRIVE
SAMPLE
DRIVE
DRIVE
–3
–3
–3
CC
CC
CC
0
0
0
= 5V
= 5V
= 5V
= 2.5V
= 2.5V
= 2.5V
= 200kSPS
= 100kSPS
= 50kSPS
–2
–2
–2
3
0
0
131
–1
80
–1
19
–1
CODE (LSB)
CODE (LSB)
CODE (LSB)
1148
1262
928
0
0
0
887
804
764
1
1
1
97
16
2
2
3
2
2
3
0
3
0
3
Rev. 0 | Page 30 of 36
1400
1200
1000
1400
1200
1000
1600
1400
1200
1000
1600
1400
1200
1000
800
600
400
200
800
600
400
200
800
600
400
200
800
600
400
200
Figure 52. Histogram of Codes—OS × 8 (Three Codes)
Figure 53. Histogram of Codes—OS × 16 (Two Codes)
Figure 54. Histogram of Codes—OS × 32 (Two Codes)
Figure 55. Histogram of Codes—OS × 64 (Two Codes)
0
0
0
0
OVERSAMPLING BY 8
F
AV
V
OVERSAMPLING BY 16
F
AV
V
OVERSAMPLING BY 32
F
AV
V
OVERSAMPLING BY 64
F
AV
V
SAMPLE
SAMPLE
SAMPLE
SAMPLE
DRIVE
DRIVE
DRIVE
DRIVE
–3
–3
–3
–3
CC
CC
CC
CC
0
0
0
0
= 5V
= 5V
= 5V
= 5V
= 2.5V
= 2.5V
= 2.5V
= 2.5V
= 25kSPS
= 12.5kSPS
= 6.125kSPS
= 3kSPS
–2
–2
–2
–2
0
0
0
0
–1
–1
–1
–1
2
0
0
0
CODE (LSB)
CODE (LSB)
CODE (LSB)
CODE (LSB)
1263
1453
1417
1679
0
0
0
0
783
595
631
369
1
1
1
1
0
2
0
2
0
2
0
2
0
3
0
3
0
3
0
3