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Preprocessing

7Acquired

Data

7

7m asu

e

rementsinput

intotemporaryarray

Sortby

descendingorder

7

Averagingoutp t

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fromwindowof3

3

TSC2007

SBAS405 – MARCH 2007

OVERVIEW (continued)

The TSC2007 has a combined MAV filter (median value filter and averaging filter).

MAV Filter

In case the acquired signal source is noisy because of the digital switching circuit, it may necessary to evaluate

the data without noise. In this case, the median value filter operation helps remove the noise. The array of seven

converted results is sorted first. The middle three values are then averaged to produce the output value of the

MAV filter.

The MAV filter is applied to all measurments for all analog inputs including the touch screen inputs, temperature

measurements TEMP1 and TEMP2, and auxiliary input AUX. To shorten the conversion time, the MAV filter may

be bypassed though the setup command; see Table 3 and Table 4.

Figure 28. MAV Filter Operation

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