Datasheet

AD7608 Data Sheet
Rev. A | Page 16 of 32
80
85
90
95
100
105
10
100
1k 10k
100k
SNR (dB)
INPUT FREQUENCY (Hz)
AV
CC
, V
DRIVE
= 5V
f
SAMPLE
CHANGES WITH OS RATE
T
A
= 25°C
INTERNAL REFERENCE
±5V RANGE
OS × 64
OS × 32
OS × 16
OS × 8
OS × 4
OS × 2
NO OS
08938-120
Figure 20. SNR vs. Input Frequency for Different Oversampling Rates, ±5 V Range
–40
–50
–60
–70
–80
–90
–100
–110
1k 100k10k
–120
THD (dB)
INPUT FREQUENCY (Hz)
±10V RANGE
AV
CC
, V
DRIVE
= 5V
f
SAMPLE
= 200kSPS
R
SOURCE
MATCHED ON Vx AND VxGND INPUTS
105kΩ
48.7kΩ
23.7kΩ
10kΩ
5kΩ
1.2kΩ
100Ω
51Ω
0Ω
08938-021
Figure 21. THD vs. Input Frequency for Various Source Impedances, ±10 V Range
1k 100k10k
THD (dB)
INPUT FREQUENCY (Hz)
±5V RANGE
AV
CC
, V
DRIVE
= 5V
f
SAMPLE
= 200kSPS
R
SOURCE
MATCHED ON Vx AND VxGND INPUTS
105kΩ
48.7kΩ
23.7kΩ
10kΩ
5kΩ
1.2kΩ
100Ω
51Ω
0Ω
–40
–50
–60
–70
–80
–90
–100
–110
–120
08938-122
Figure 22. THD vs. Input Frequency for Various Source Impedances, ±5 V Range
4.0
–40 –25 –10 5 20 35 50 65 80
–4.0
–3.2
–2.4
–1.6
–0.8
0
0.8
1.6
2.4
3.2
BIPOLAR ZERO CODE ERROR (LSB)
TEMPERATURE (°C)
200kSPS
AV
CC
, V
DRIVE
= 5V
EXTERNAL REFERENCE
±5V RANGE
±10V RANGE
08938-023
Figure 23. Bipolar Zero Code Error vs. Temperature
16
12
8
4
0
–4
–8
–12
–40 –25 –10 5 20 35 50 65 80
–16
BIPOLAR ZERO CODE ERROR MATCHING (LSB)
TEMPERATURE (°C)
200kSPS
AV
CC
, V
DRIVE
= 5V
EXTERNAL REFERENCE
±5V RANGE
±10V RANGE
08938-024
Figure 24. Bipolar Zero Code Error Matching Between Channels
–50
–60
–70
–80
–90
–100
–110
–120
–130
0 16014012010080604020
–140
CHANNEL-TO-CHANNEL ISOLATION (dB)
NOISE FREQUENCY (kHz)
±10V RANGE
±5V RANGE
AV
CC
, V
DRIVE
= 5V
INTERNAL REFERENCE
AD7608 RECOMMENDED DECOUPLING USED
f
SAMPLE
= 150kSPS
T
A
= 25°C
INTERFERER ON ALL UNSELECTED CHANNELS
08938-025
Figure 25. Channel-to-Channel Isolation