DocID17613 Rev 3

7/15

AN3236

Combined implementation

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Combined implementation

Combined implementation (see Figure 2) allows any touchkey from set 1, 2 or 3 to be

touched simultaneously but, if two touchkeys from within the same set are touched

concurrently, an incorrect touchkey is detected. For instance, touchkeys 1, 6 and 8 can be

touched by the user at the same time and the application decodes them correctly but, if

touchkeys 2 and 3 are touched simultaneously only touchkey 3 is reported. Likewise, if

touchkeys 4 and 5 are touched concurrently, touchkey 6 is incorrectly reported.

Figure 2. Combined implementation example for multi-touch capability

1. A set consists of three touchkeys acquired through two channels.