Datasheet

AD7949 Data Sheet
Rev. D | Page 12 of 32
–
60
–70
–80
–90
–100
–110
–120
0 50 100 150 200
THD (dB)
FREQUENCY (kHz)
VDD = V
REF
= 5V, –0.5dB
VDD = V
REF
= 2.5V, –0.5dB
VDD = V
REF
= 2.5V, –10dB
VDD = V
REF
= 5V, –10dB
07351-017
Figure 17. THD vs. Frequency
90
89
88
87
86
85
84
83
82
81
80
79
78
–10
SNR (dB)
INPUT LEVEL (dB)
–8 –6 –2 0–4
f
IN
= 20kHz
VDD = V
REF
= 2.5V
07351-018
VDD = V
REF
= 5V
Figure 18. SNR vs. Input Level
2
1
0
–1
–2
OFFSET ERROR AND GAIN ERROR (LSB)
–55
TEMPERATURE (°C)
–35 –15 5 25 45 65 85 105
125
UNIPOLAR ZERO
UNIPOLAR GAIN
BIPOLAR ZERO
BIPOLAR GAIN
07351-019
Figure 19. Offset and Gain Errors vs. Temperature
2750
2500
2250
2000
1750
1500
1250
1000
750
100
90
80
70
60
50
40
30
20
2.5 3.0 3.5 4.0 4.5 5.0 5.5
VDD CURRENT (µA)
VIO CURRENT (µA)
VDD SUPPLY (V)
2.5V INTERNAL REF
4.096V INTERNAL REF
INTERNAL BUFFER, TEMP ON
INTERNAL BUFFER, TEMP OFF
EXTERNAL REF, TEMP ON
EXTERNAL REF, TEMP OFF
VIO
f
S
= 200kSPS
07351-020
Figure 20. Operating Currents vs. Supply
3000
2750
2500
2250
2000
1750
1500
1250
1000
180
160
140
120
100
80
60
40
20
VDD CURRENT (µA)
VIO CURRENT (µA)
–55
TEMPERATURE (°C)
–35 –15 5 25 45 65 85 105
125
f
S
= 200kSPS
VDD = 5V, INTERNAL 4.096V REF
VDD = 5V, EXTERNAL REF
VDD = 2.5, EXTERNAL REF
VIO
07351-021
Figure 21. Operating Currents vs. Temperature
SDO CAPACITIVE LOAD (pF)
1200 20406080100
t
DSDO
DELAY (ns)
25
20
15
10
5
0
VDD = 2.5V, 85°C
VDD = 3.3V, 25°C
VDD = 3.3V, 85°C
VDD = 5V, 85°C
VDD = 5V, 25°C
VDD = 2.5V, 25°C
07351-022
Figure 22. t
DSDO
Delay vs. SDO Capacitance Load and Supply