Touch-controlled assembly

A touch-controlled assembly, adapted to an electronic device, the electronic device having a front casing, a rear casing and a display surface, wherein the display surface is located on the front casing, the touch-controlled assembly comprising:

• a circuit board, disposed between the front casing and the rear casing, and having at least one pad, wherein the at least one pad contacts one surface of the rear casing;
• and
• at least one touch key, disposed on another surface of the rear casing for corresponding to the at least one pad, wherein the rear casing is located between the at least one pad and the at least one touch key without a gap and without other medium therebetween, an orthogonal projection of the at least one touch key on the at least one pad is only partially overlapped with the at least one pad, the at least one touch key extends further than the at least one pad in a first direction towards an outer edge of the rear casing, the at least one pad extends further than the at least one touch key in a second direction opposite to the first direction, the orthogonal projection of the at least one touch key on the at least one pad that is not overlapped with the at least one pad is an extending region of a touch region of the touch key extending towards the outer edge of the rear casing, so that the extending region can be smoothly touched, wherein the rear casing has a rib that overlaps the extending region, and
• wherein an overlapped area between an orthogonal projection area of the at least one touch key on the circuit board and an area of the at least one pad is greater than or equal to 40% of the area of the at least one pad.