AD7794 Analog Devices, AD7794 Datasheet - Page 16

• Manufacturer Part Number: AD7794
• Description: 6-Channel, Low Noise, Low Power, 24-Bit Sigma Delta ADC with On-Chip In-Amp and Reference
• Manufacturer: Analog Devices

Specifications of AD7794

• Resolution (bits): 24bit
• # Chan: 6
• Sample Rate: n/a
• Interface: Ser,SPI
• Analog Input Type: Diff-Uni
• Ain Range: (2Vref/PGA Gain) p-p
• Adc Architecture: Sigma-Delta
• Pkg Type: SOP

AD7794/AD7795
TYPICAL PERFORMANCE CHARACTERISTICS
Figure 7. Noise Distribution Histogram for the AD7794 (Internal Reference,
8388800
8388750
8388700
8388650
8388600
8388550
8388500
8388450
8388450
8388400
8388350
8388300
8388250
8388200
8388150
8388100
8388050
Gain = 64, Update Rate = 16.7 Hz, AMP-CM = 1, Chop Disabled)
Figure 6. Typical Noise Plot for the AD7794 (Internal Reference,
Figure 8. Typical Noise Plot for the AD7794 (Internal Reference,
16
14
12
10
8388482
8
6
4
2
0
0
0
Gain = 64, Update Rate = 16.7 Hz, Chop Enabled)
Gain = 64, Update Rate = 16.7 Hz, Chop Enabled)
8388520
200
200
8388560
READING NUMBER
READING NUMBER
8388600
400
400
CODE
8388640
600
600
8388680
800
800
8388720
8388750
1000
1000
Rev. D | Page 16 of 36
Figure 9. Noise Distribution Histogram for the AD7794 (Internal Reference,
Figure 10. Excitation Current Matching (210 μA) at Ambient Temperature
Figure 11. Bias Voltage Generator Power-Up Time vs. Load Capacitance
Gain = 64, Update Rate = 16.7 Hz, Chop Disabled, AMP-CM = 1)
14
12
10
20
10
90
80
70
60
50
40
30
20
10
8388068
8
6
4
2
0
0
0
0
–2.0
8388100
–1.2
200
8388150
–0.8
BOOST = 1
LOAD CAPACITANCE (nF)
–0.4
BOOST = 0
8388200
400
MATCHING (%)
0
CODE
8388250
0.4
600
0.8
8388300
1.2
800
8388350
1.6
2.0
8388396
1000