Data Sheet
AD7949
Rev. D | Page 11 of 32
90
85
80
75
70
65
60
0
50
100
150
200
S
NR
(
d
B)
FREQUENCY (kHz)
VDD = VREF = 5V, –0.5dB
VDD = VREF = 5V, –10dB
VDD = VREF = 2.5V, –0.5dB
VDD = VREF = 2.5V, –10dB
07351-
011
Figure 11. SNR vs. Frequency
88
86
84
82
80
78
15.5
15.0
14.5
14.0
13.5
13.0
1.0
S
NR,
S
INAD
(
d
B)
E
NO
B
(
Bi
ts)
REFERENCE VOLTAGE (V)
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SNR
SINAD
ENOB
07351-
012
Figure 12. SNR, SINAD, and ENOB vs. Reference Voltage
90
85
80
75
70
65
60
–55
S
NR
(
d
B)
TEMPERATURE (°C)
–35
–15
5
25
45
65
85
105
125
fIN = 20kHz
VDD = VREF = 5V
VDD = VREF = 2.5V
07351-
013
Figure 13. SNR vs. Temperature
90
85
80
75
70
65
60
0
50
100
150
200
S
INAD
(
d
B)
FREQUENCY (kHz)
VDD = VREF = 5V, –0.5dB
VDD = VREF = 5V, –10dB
VDD = VREF = 2.5V, –0.5dB
VDD = VREF = 2.5V, –10dB
07351-
014
Figure 14. SINAD vs. Frequency
130
125
120
115
110
105
100
95
90
85
80
75
70
1.0
S
F
DR
(
d
B)
–60
–65
–70
–75
–80
–85
–90
–95
–100
–105
–110
–115
–120
T
HD
(
d
B)
REFERENCE VOLTAGE (V)
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SFDR
THD
07351-
015
Figure 15. SFDR and THD vs. Reference Voltage
–90
–95
–100
–105
–110
–55
T
HD
(
d
B)
TEMPERATURE (°C)
–35
–15
5
25
45
65
85
105
125
fIN = 20kHz
VDD = VREF = 5V
VDD = VREF = 2.5V
07351-
016
Figure 16. THD vs. Temperature