AD7156 Analog Devices, AD7156 Datasheet - Page 8

• Manufacturer Part Number: AD7156
• Manufacturer: Analog Devices

Specifications of AD7156

• Resolution (bits): 12bit
• # Chan: 2
• Sample Rate: 100SPS
• Interface: I²C/Ser 2-Wire,Ser
• Analog Input Type: Capacitive
• Ain Range: 0.5 pF,1 pF,2 pF,4 pF
• Pkg Type: CSP

AD7156
TYPICAL PERFORMANCE CHARACTERISTICS
Figure 4. Capacitance Input Offset Error vs. Capacitance CIN to GND,
Figure 5. Capacitance Input Gain Error vs. Capacitance CIN to GND,
Figure 6. Capacitance Input Gain Error vs. Capacitance CIN to GND,
–10
–15
–20
–25
–10
–15
–20
–25
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
–5
–5
0
5
0
5
0
0
0
0
V
DD
V
V
DD
DD
50
50
50
= 1.8 V and 3.3 V, EXC Pin Open Circuit
= 1.8 V and 3.3 V, CIN to EXC = 3 pF
= 1.8 V and 3.3 V, CIN to EXC = 9 pF
CAPACITANCE CIN TO GROUND (pF)
CAPACITANCE CIN TO GROUND (pF)
CAPACITANCE CIN TO GROUND (pF)
1.8V
100
100
100
1.8V
1.8V
150
150
150
3.3V
200
200
200
3.3V
3.3V
250
250
250
300
300
300
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Figure 7. Capacitance Input Offset Error vs. Capacitance EXC to GND,
Figure 8. Capacitance Input Gain Error vs. Capacitance EXC to GND,
Figure 9. Capacitance Input Gain Error vs. Capacitance EXC to GND,
–1
–2
–3
–4
–1
–2
–3
–4
–1
–2
–3
–4
1
0
1
0
1
0
0
0
0
V
DD
V
V
DD
DD
= 1.8 V and 3.3 V, CIN Pin Open Circuit
= 1.8 V and 3.3 V, CIN to EXC = 3 pF
= 1.8 V and 3.3 V, CIN to EXC = 9 pF
CAPACITANCE EXC TO GROUND (pF)
CAPACITANCE EXC TO GROUND (pF)
CAPACITANCE EXC TO GROUND (pF)
500
500
500
1000
1000
1000
1500
1500
1500
1.8V
1.8V
1.8V
3.3V
3.3V
3.3V
2000
2000
2000