2 Button Attachment

The button attachment module is a simple platform that clips into the BOOST-LDC3114EVM coils. It is a 3D printed plastic part that uses copper tape to provide a target for the LDC3114. The copper tape is placed on the coil side of the plastic so that as force is applied to the flat surface, the copper bends slightly towards the coil.

Figure 2-1 LDC3114EVM Button Attachment

Figure 2-2 Button Attachment Metal Placement

This is a simple example of how a button application can work with the LDC3114. Pressing on the flat surface causes the copper tape to deflect towards the sensor. The impact of this can be seen by monitoring the data with the LDC3114EVM GUI or watching the LEDs on the EVM to see the digital button output. In the data graph, the button data fluctuates at the start of the press. Cases like this can happen when pressing the button, so it is important to consider adjusting the hysteresis settings in the devices button algorithm. More information about the button algorithm settings can be found in the internal algorithm functionality app note. Using hysteresis, this example of a button press shows a clear digital output correlating to the button data.

Figure 2-3 Button Attachment Data