3.6 Lump

The Lump feature allows multiple buttons to be combined (or Lumped) to form a single button. The Lump feature is useful to:

  • Reduce the number of sensors by combining multiple buttons, which helps in power consumption

  • Form a large touch surface using small buttons, thus increasing the sensitivity, which helps to realize proximity sensing. Proximity sensing requires a large electrode area to detect an approaching hand. Lumping the keypad's corner keys can help to detect approaching hand and wake the system up. In the keypad example, the low-power Lump (created out of existing keys of the keypad) is the only entity scanned in sleep, waking the system up by user proximity, exemplary back-lighting the keypad. After waking, all keypad buttons are scanned.