AD7142
PLASTIC OVERLAY
SENSOR BOARD
CAPACITIVE SENSOR
CIN
CBULK
Figure 2.
Table 2. Typical Average Current in Low Power Mode, AVCC, DVCC = 3.6 V, T= 25°C, Load of 50 pF on SRC Pin, No Load on SRC
Number of Conversion Stages (Current Values Expressed in μA)
Low Power Mode Decimation
Delay
Rate
1
2
3
4
5
6
7
8
9
10 11
200 ms
128
26.4 33.3 40.1 46.9 53.5 60 66.5 72.8 79.1 85.2 91.3
256
35.6 49.1 62.2 74.9 87.3 99.3 111 122.3 133.4 144.2 154.7
400 ms
128
21.3 24.8 28.3 31.7 35.2 38.6 42 45.4 48.7 52 55.3
256
26 32.9 39.7 46.5 53.1 59.6 66.1 72.4 78.7 84.9 91
600 ms
128
19.6 21.9 24.3 26.6 28.9 31.2 33.5 35.8 38.1 40.4 42.6
256
22.7 27.4 32 36.6 41.1 45.6 50 54.4 58.8 63.1 67.4
800 ms
128
18.7 20.5 22.2 24 25.7 27.5 29.2 31 32.7 34.4 36.1
256
21.1 24.6 28.1 31.5 35 38.4 41.8 45.2 48.5 51.8 55.1
12
97.3
164.9
58.6
97
44.8
71.6
37.8
58.4
Table 3. Maximum Average Current in Low Power Mode, AVCC, DVCC = 3.6 V, Load of 50 pF on SRC Pin, No Load on SRC
Number of Conversion Stages (Current Values Expressed in μA)
Low Power Mode Decimation
Delay
Rate
1
2
3
4
5
6
7
8
9
10 11
200 ms
128
45.4 53.6 61.5 69.4 77.1 84.7 92.2 99.6 106.8 113.9 121
256
56.2 72 87.2 102 116.3 130.2 143.7 156.8 169.5 181.8 193.8
400 ms
128
39.5 43.6 47.7 51.8 55.8 59.8 63.7 67.6 71.5 75.4 79.2
256
45 53.1 61.1 68.9 76.7 84.3 91.8 99.1 106.4 113.6 120.6
600 ms
128
37.5 40.3 43 45.8 48.5 51.2 53.9 56.5 59.2 61.8 64.5
256
41.2 46.7 52.1 57.4 62.7 67.9 73.1 78.2 83.3 88.3 93.3
800 ms
128
36.5 38.6 40.7 42.7 44.8 46.8 48.8 50.9 52.9 54.9 56.9
256
39.3 43.4 47.5 51.5 55.6 59.5 63.5 67.4 71.3 75.2 79
12
127.9
205.5
83
127.5
67.1
98.2
58.9
82.8
Rev. A | Page 5 of 72