Power/Reset Click Board™

The Power/Reset Click Board™ has two PCB pads, used to sense touch or proximity events. These pads are the only elements on the top of the board, allowing installation of the protective acrylic glass layer. These pads are marked as ON/OFF and RESET in order to offer to a user a simple solution for a capacitive switching power and reset controls for various devices. This click board™ includes all hardware and signal processing functions necessary to provide stable sensing under a wide variety of changing conditions.

How Does The Power/Reset Click Board™ Work?

The Power/Reset Click Board™ is a capacitive touch sensing Click board™ which features the QT1011, digital burst mode charge-transfer sensor that is capable of detecting near proximity or touch, from Microchip. This click board™ has two PCB pads, used to sense touch or proximity events. Besides the two touch sensitive pads, Power/Reset click has two LED diodes for the touch indication. The two touch pads use two separate QT1011 ICs, providing a very reliable touch sensing functionality.

The AT42QT1011 is a digital burst mode charge-transfer sensor that is capable of detecting nearproximity or touch, making it ideal for implementing touch controls. With the proper electrode and circuit design, the self-contained digital IC will project a touch or proximity field to several centimeters through any dielectric like glass, plastic, stone, ceramic, and even most kinds of wood. It can also turn small metal-bearing objects into intrinsic sensors, making them responsive to proximity or touch. This capability, coupled with its ability to self-calibrate, can lead to entirely new product concepts.

The QT1011 is designed specifically for human interfaces like control panels, appliances, toys, lighting controls, or anywhere a mechanical switch or button may be found. It includes all hardware and signal processing functions necessary to provide stable sensing under a wide variety of changing conditions. However, this click board™ is designed to serve as a power and reset capacitive switch panel board.

Besides the QT1011, the Power/Reset Click Board™ contains 74LVC1G74 as well. It is a Single D-type flip-flop with set and reset. Because The output of the QT1011 is active-high upon detection, the 74LVC1G74 is triggered by the positive edge of the ON/OFF touch pad. It is wired in a cascade with the QT1011 in way that ensures holding one logical state until the ON/OFF pad is pressed. Therefore, the ON/OFF pad acts like a switch, while the RESET pad acts like a button, which is suitable for most common purposes.

The output signals for the ON/OFF and RESET pads are wired to the PWM and INT pins on the mikroBUS™, respectively. Besides that, the STAT and RST LEDs are wired parallel to the outputs in order to ensure a visible indication of the status of the pins.

The Power/Reset Click Board™ is designed to be operated only with 3.3V logic level. A proper logic voltage level conversion should be performed before the Click board™ is used with MCUs with logic levels of 5V.

SPECIFICATIONS

PINOUT DIAGRAM

This table shows how the pinout on Power/Reset Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

ONBOARD SETTINGS AND INDICATORS