AD7873 Analog Devices, AD7873 Datasheet - Page 10

• Manufacturer Part Number: AD7873
• Description: Touch Screen Digitizer
• Manufacturer: Analog Devices

Specifications of AD7873

• Resolution (bits): 12bit
• # Chan: 6
• Sample Rate: 125kSPS
• Interface: Ser
• Analog Input Type: SE-Uni
• Ain Range: Uni (Vref),Uni 2.5V
• Adc Architecture: SAR
• Pkg Type: CSP,SOP

AD7873
7.5
6.5
5.5
4.5
3.5
2.5
1.5
0.5
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
10
9
8
7
6
5
4
0
Figure 13. Linearity Error vs. Sampling Rate for Various R
10
2.0
15
Figure 11. Reference Current vs. Sample Rate
35
Y+
25
Figure 12. Switch On Resistance vs. +V
2.5
(X+, Y+: +V
X–
X+
55
40
INL: R = 500Ω
3.0
DNL: R = 2kΩ
SAMPLING RATE (kSPS)
Y–
75
CC
SAMPLE RATE (kHz)
55
to Pin; X−, Y−: Pin to GND)
DNL: R = 500Ω
3.5
95
+V
CC
70
(V)
115
4.0
85
135
INL: R = 2kΩ
4.5
100
155
CC
5.0
115
175
IN
130
195
5.5
Rev. E | Page 10 of 28
2.5006
2.5004
2.5002
2.5000
2.4998
2.4996
2.4994
2.4992
2.4990
2.4988
14
13
12
11
10
9
8
7
6
5
4
3
–40
9
8
7
6
5
4
3
2
–40
–40 –30 –20 –10
Figure 15. Switch On Resistance vs. Temperature
Figure 14. Reference Current vs. Temperature
(X+, Y+: +VCC to Pin; X−, Y−: Pin to GND)
–20
Figure 16. Internal V
–20
0
Y–
0
TEMPERATURE (°C)
0
TEMPERATURE (°C)
TEMPERATURE (°C)
20
10
20
REF
Y+
20
vs. Temperature
40
30
X–
40
40
60
50
60
X+
60
80
70
80
100
80