Datasheet
AD7457
Rev. A | Page 8 of 20
TYPICAL PERFORMANCE CHARACTERISTICS
T
A
= 25°C, f
S
= 100 kSPS, f
SCLK
= 10 MHz, V
DD
= 2.7 V to 5.25 V, V
REF
= 2.5 V, unless otherwise noted.
FREQUENCY (kHz)
65
10
SINAD (dB)
20 50
70
75
V
DD
= 3V
30 40
V
DD
= 5V
03157-0-014
Figure 5. SINAD vs. Analog Input Frequency for V
DD
= 3 V and 5 V
0
–20
–40
–80
–60
–120
–100
–140
03157-0-015
SUPPLY RIPPLE FREQUENCY (kHz)
0 100 200 300 400 500
PSRR (dB)
900 1000
V
DD
= 5V
V
DD
= 3V
100mV p-p SINEWAVE ON V
DD
NO DECOUPLING ON V
DD
600 700 800
Figure 6. PSRR vs. Supply Ripple Frequency Without Supply Decoupling
FREQUENCY (kHz)
SNR (dB)
0
–20
–40
–80
–60
–120
–100
–140
0 100
8192 POINT FFT
f
SAMPLE
= 100kSPS
f
IN
= 30kHz
SINAD = 71dB
THD = –82dB
SFDR = –83dB
03157-0-016
30 50
Figure 7. Dynamic Performance for V
DD
= 5 V
CODE
DNL ERROR (LSB)
1.0
0.8
0.6
0.2
0.4
–0.2
–0.4
–0.6
–0.8
0
–1.0
0 1024 30722048 4096
03157-0-017
Figure 8. Typical DNL for the AD7457 for V
DD
= 5 V
CODE
INL ERROR (LSB)
1.0
0.8
0.6
0.2
0.4
–0.2
–0.4
–0.6
–0.8
0
–1.0
0 1024 30722048 4096
03157-0-018
Figure 9. Typical INL for the AD7457 for V
DD
= 5 V
CODES
0
2046 2047 2048 2049 2050 2051
27 CODES 24 CODES
9949
CODES
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
03157-0-019
COUNTS
Figure 10. Histogram of 10,000 Conversions of a DC Input