AD7321 Analog Devices, AD7321 Datasheet - Page 12

• Manufacturer Part Number: AD7321
• Description: 500 kSPS, 2-Channel, Software-Selectable, True Bipolar Input, 12-Bit Plus Sign ADC
• Manufacturer: Analog Devices

Specifications of AD7321

• Resolution (bits): 13bit
• # Chan: 2
• Sample Rate: 500kSPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Uni,SE-Uni
• Ain Range: Bip 10V,Bip 2.5V,Bip 5.0V,Uni 10V
• Adc Architecture: SAR
• Pkg Type: SOP

AD7321
–100
–50
–55
–60
–65
–70
–75
–80
–85
–90
–95
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
8k
7k
6k
5k
4k
3k
2k
1k
0
0
0
5
Figure 17. CMRR vs. Common-Mode Ripple Frequency
±5V RANGE
V
INTERNAL REFERENCE
SINGLE-ENDED MODE
Figure 16. Histogram of Codes, Single-Ended Mode
Figure 18. DNL Error vs. Supply Voltage at 500 kSPS
V
CC
–3
CC
0
= V
= 5V
V
200
7
CC
DRIVE
= 3V
23
–2
= 5V
±V
RIPPLE FREQUENCY (kHz)
9
DD
400
1201
/V
–1
SS
SUPPLY VOLTAGE (V)
11
CODE
600
7600
0
DNL = 500kSPS
13
DIFFERENTIAL MODE
F
V
f
T
S
IN
DD
A
1165
= 500kSPS
= 25°C
800
= 50kHz
1
/V
SS
V
V
RANGE = ±10V
10k SAMPLES
T
15
A
CC
DD
= ±12V
= 25°C
/V
= 5V
11
2
1000
SS
= ±12V
17
0
3
1200
19
Rev. A | Page 12 of 36
Figure 21. THD vs. Analog Input Frequency for Various Source Impedances,
Figure 20. PSRR vs. Supply Ripple Frequency Without Supply Decoupling
–100
–100
–0.5
–1.0
–1.5
–2.0
–50
–55
–60
–65
–70
–75
–80
–85
–90
–95
–50
–55
–60
–65
–70
–75
–80
–85
–90
–95
2.0
1.5
1.0
0.5
0
10
0
5
V
V
T
INTERNAL REF
RANGE = ±10V AND ±2.5V
f
DIFFERENTIAL MODE
100mV p-p SINE WAVE ON EACH SUPPLY
NO DECOUPLING
SINGLE-ENDED MODE
f
S
S
A
Figure 19. INL Error vs. Supply Voltage at 500 kSPS
CC
DD
= 500kSPS
= 500kSPS
= 25°C
/V
= V
SS
200
DRIVE
7
= ±12V
SUPPLY RIPPLE FREQUENCY (kHz)
= 5V
±V
True Differential Mode
9
DD
INPUT FREQUENCY (kHz)
400
/V
SS
SUPPLY VOLTAGE (V)
11
INL = 500kSPS
600
100
13
±5V RANGE
V
INTERNAL REFERENCE
SINGLE-ENDED MODE
V
V
CC
CC
V
800
DD
SS
= V
= 3V
= 12V
15
= –12V
±10V RANGE
R
R
R
R
R
R
±2.5V RANGE
R
R
R
R
R
DRIVE
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
V
= 4000Ω
= 3000Ω
= 2000Ω
= 1000Ω
= 100Ω
= 12Ω
1000
= 9000Ω
= 5500Ω
= 2000Ω
= 100Ω
= 12Ω
CC
= 5V
17
= 5V
1200
1000
19