Datasheet

Data Sheet AD7949
Rev. D | Page 11 of 32
90
85
80
75
70
65
60
0 50 100 150 200
SNR (dB)
FREQUENCY (kHz)
VDD = V
REF
= 5V, –0.5dB
VDD = V
REF
= 5V, –10dB
VDD = V
REF
= 2.5V, –0.5dB
VDD = V
REF
= 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
SNR, SINAD (dB)
ENOB (Bits)
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
SNR (dB)
TEMPERATURE (°C)
–35 –15 5 25 45 65 85 105
125
f
IN
= 20kHz
VDD = V
REF
= 5V
VDD = V
REF
= 2.5V
07351-013
Figure 13. SNR vs. Temperature
90
85
80
75
70
65
60
0 50 100 150 200
SINAD (dB)
FREQUENCY (kHz)
VDD = V
REF
= 5V, –0.5dB
VDD = V
REF
= 5V, –10dB
VDD = V
REF
= 2.5V, –0.5dB
VDD = V
REF
= 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
SFDR (dB)
–60
–65
–70
–75
–80
–85
–90
–95
–100
–105
–110
–115
–120
THD (dB)
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
THD (dB)
TEMPERATURE (°C)
–35 –15 5 25 45 65 85 105
125
f
IN
= 20kHz
VDD = V
REF
= 5V
VDD = V
REF
= 2.5V
07351-016
Figure 16. THD vs. Temperature