Carbon Pill Keypads Silicone Keypad Button

Carbon pill keypads incorporate conductive contact features beneath the molded keys. When a key is pressed in the intended assembly, its contact must meet the corresponding board area correctly. This construction is used in controls such as remote handsets and calculators, where a flexible key surface and a repeatable electrical response need to work together.

The underside deserves as much attention as the visible layout. The pill position, contact footprint and resting clearance should match the circuit design. A key that appears centered in the front opening can still press the board unevenly if the locating features permit the rubber to shift. Check alignment with the housing fully assembled, not just with the keypad laid loosely over the board.

ETOL can customize the molded structure, dimensions, hardness, color and marking. Electrical acceptance should follow the intended circuit requirements. A new key shape should also be checked for how it brings the conductive face into contact, particularly when a user presses near the side of a larger key.

Keep the conductive surfaces clean during assembly. Avoid touching them with oily fingers or placing the keypad contact-side down on a dusty workbench. When troubleshooting an inconsistent input, examine seating and contamination before changing the force applied to the key. Scraping the contact face or adding an unspecified coating can change the interface rather than restore it.

Approve carbon pill keypads using the actual board and enclosure together. Confirm that each input releases when the key returns, and that adjacent controls remain inactive. This verifies the conductive contact in the same mechanical arrangement that will be used in the finished product.

Material options

Silicone. Custom formulation and color for the intended contact conditions.

Hardness selection

Silicone: 20–80 Shore A. Confirm that each input releases when the key returns, and that adjacent controls remain inactive.

Custom dimensions

A key that appears centered in the front opening can still press the board unevenly if the locating features permit the rubber to shift.

Fit & assembly

Check alignment with the housing fully assembled, not just with the keypad laid loosely over the board.

Use & inspection

When a key is pressed in the intended assembly, its contact must meet the corresponding board area correctly.

Photos illustrate structure or material only. The pill position, contact footprint and resting clearance should match the circuit design. ETOL directly manufactures custom-shaped silicone and rubber parts to your requirements.