AD7608 Analog Devices, AD7608 Datasheet - Page 15

• Manufacturer Part Number: AD7608
• Description: 8-Channel DAS with 18-Bit, Bipolar, Simultaneous Sampling ADC
• Manufacturer: Analog Devices

Specifications of AD7608

• Resolution (bits): 18bit
• # Chan: 8
• Sample Rate: 200kSPS
• Interface: Par,Ser,SPI
• Analog Input Type: Diff-Bip
• Ain Range: Bip 10V,Bip 5.0V
• Adc Architecture: SAR
• Pkg Type: QFP

Data Sheet
–0.1
–0.2
–0.3
–0.4
–0.5
–0.6
–0.7
–0.8
–0.9
–1.0
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
–20
–40
–60
–80
–20
–40
–60
–80
80
60
40
20
80
60
40
20
0
0
0
–40
–40
–25
–25
Figure 15. NFS Error vs. Temperature
Figure 16. PFS Error vs. Temperature
Figure 14. Typical DNL, ±5 V Range
–10
–10
TEMPERATURE (°C)
TEMPERATURE (°C)
5
5
CODE
20
20
AV
INTERNAL REFERENCE
f
T
±5V RANGE
35
35
SAMPLE
200kSPS
AV
EXTERNAL REFERENCE
200kSPS
AV
EXTERNAL REFERENCE
A
CC
= 25°C
CC
CC
±10V RANGE
±10V RANGE
, V
, V
, V
50
50
DRIVE
= 200 kSPS
DRIVE
DRIVE
±5V RANGE
±5V RANGE
= 5V
= 5V
= 5V
65
65
80
80
Rev. A | Page 15 of 32
Figure 19. SNR vs. Input Frequency for Different Oversampling Rates, ±10 V Range
105
100
95
90
85
80
–16
–24
–32
–40
10
–2
40
32
24
16
–8
8
6
4
2
0
10
8
0
–40
0
NFS ERROR
OS × 64
OS × 32
OS × 16
NO OS
OS × 8
OS × 4
OS × 2
Figure 18. PFS/NFS Error vs. Source Resistance
PFS ERROR
–25
20k
Figure 17. NFS/PFS Error Matching
100
–10
SOURCE RESISTANCE (Ω)
INPUT FREQUENCY (Hz)
40k
AV
f
T
EXTERNAL REFERENCE
SOURCE RESISTANCE IS MATCHED ON
THE VxGND INPUT
±10V AND ±5V RANGE
SAMPLE
A
TEMPERATURE (°C)
5
CC
= 25°C
AV
f
T
INTERNAL REFERENCE
±10V RANGE
SAMPLE
A
, V
CC
= 25°C
DRIVE
60k
, V
= 200 kSPS
1k
20
DRIVE
CHANGES WITH OS RATE
= 5V
35
±10V RANGE
AV
EXTERNAL REFERENCE
= 5V
80k
CC
, V
10k
50
DRIVE
100k
= 5V
65
AD7608
80
100k
120k