This is a simple touch sensor module. You can use it to replace a traditional push button. Using the TTP223-B touch detector IC It measures the capacitance of a metallic pad. It can detect the change in capacitance when a finger is near it. This is the same technology used in the iPhone touch screen. So you can place the metallic pad under a non-metallic surface such as a plastic or glass sheet and it will still work as a button. This may be useful for projects that need to be waterproof. You can also make a secret button by placing it inconspicuously behind a smooth surface. For instance, you could place them under a nonmetallic card table and by casually pressing the right location on a tabletop surface you could mysteriously control your DIY project. 

Features 

• Grove compatible interface 

• 2.0-5.5V DC supply 

• response time max about 60mS at fast mode, 220mS at low power mode @VDD=3V 

• Low power consumption 

• 2.0cm x 2.0cm twig module 

• Power indicator led 

Applications

• Inconspicuous button 

• Waterproofed electric product 

• Button key replacement

For all Grove users (especially beginners), we provide you guidance PDF documents. Please download and read through Preface - Getting Started and Introduction to Grove before your using of the product.