Legacy Nxp Capacitive Touch Sensors

1. General description：

    The integrated circuit PCA8885 is a capacitive 8-channel touch and proximity sensor that uses a patented (EDISEN) method to detect a change in capacitance on remote sensing plates. Changes in the static capacitances (as opposed to dynamic capacitance changes) are automatically compensated using continuous auto-calibration. Remote sensing plates (for example, conductive foils) can be connected to the IC1 using coaxial cable. The eight input channels operate independently of each other. There is also a built-in option for a matrix arrangement of the sensors: interrupt generation only when two channels are activated simultaneously, suppression of additional channel outputs when two channels are already active.

2. Features and benefits：

• AEC-Q100 compliant for automotive applications

• Dynamic touch and proximity sensor with 8 sensor channels

• Support for matrix arrangement of sensors

• Sensing plates can be connected remotely

• Adjustable response time

• Adjustable sensitivity

    *Continuous auto-calibration

    *Digital processing method

*Can cope with up to 6 mm of acrylic glass

• Direct and latching switch modes

• I²C Fast-mode Plus (Fm+) compatible interface

    *Two I²C-bus addresses

    *Cascading of two ICs possible

    * Interrupt signaling over I²C-bus

• Interrupt output

• Large voltage operating range (VDD = 2.5 V to 5.5 V)

• Sleep mode (I_DD < 100 nA)

• Low-power battery operation possible (I_DD ~ 10μA)

• Operating temperature range (T_amb =-40℃ to +85℃)

3. Applications：

• Replacing mechanical switches

• Hermetically sealed keys on a keyboard

• Switches for medical applications

• Switches for use in explosive environments

• Audio control: on/off, channel, volume

• Vandal proof switches

• Switches in or under the upholstery, leather, handles, mats, carpets, tiles, and glass

• Use of standard metal sanitary parts (for example a tap) as switch

• Portable communication and entertainment units

• White goods control panel