How cooktop buttons works? In this picture can see circles (marks) from control board. cooktop glass from inside

Here are control board with buttons. If i touch that black "buttons", it is like dish wash sponge. Control board (part one)

How that buttons works ? Because in glass have no holes or some wires. Those black "buttons" are some special material?


Those black "buttons" are conductive foam, extending a touch sensor's conductive surface to just below the inner surface of the glass.

This allows capacitive touch or capacitive proximity sensors on the PCB, under the conductive foam, to sense touch / finger proximity on the upper side of the glass.

See this answer for some possible touch / proximity sense components, and a description of how they would work through glass.



Not the answer you're looking for? Browse other questions tagged or ask your own question.