{"product_id":"4x3-membrane-keypad-matrix-12-key-numeric-7pin-arduino","title":"4×3 Membrane Keypad Matrix — 12-Key Numeric, 7-Pin Connector, Arduino Compatible","description":"\u003ch2\u003e4×3 Membrane Keypad Matrix — 12-Key Numeric, 7-Pin Connector, Arduino Compatible\u003c\/h2\u003e\n\n\u003cp\u003eThis \u003cstrong\u003e4×3 membrane keypad\u003c\/strong\u003e provides 12 keys in the standard telephone\/calculator numeric layout (1–9, *, 0, #) — the most common keypad format for PIN entry and numeric input applications. The flexible membrane construction with adhesive backing allows it to be mounted on any flat surface, and the 7-pin ribbon cable connector makes wiring to Arduino straightforward. Compatible with the Arduino Keypad.h library.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eKeys:\u003c\/strong\u003e 12 (4 rows × 3 columns)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eKey Labels:\u003c\/strong\u003e 1–9, *, 0, # (standard telephone layout)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInterface:\u003c\/strong\u003e 7-pin ribbon cable connector\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Membrane (flexible, thin)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAdhesive Backing:\u003c\/strong\u003e Yes — peel and stick to any flat surface\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSupply Voltage:\u003c\/strong\u003e 3.3V and 5V compatible (passive matrix)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e4×3 vs 4×4 Keypad — Which to Choose?\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003e4×3 (this listing):\u003c\/strong\u003e 12 keys, standard numeric layout (0–9, *, #) — for PIN entry and numeric input\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e4×4:\u003c\/strong\u003e 16 keys, adds A\/B\/C\/D function keys — for hex input and multi-function control\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eArduino Wiring (Keypad.h Library)\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eConnect 7-pin ribbon cable to Arduino digital pins (e.g., D2–D8)\u003c\/li\u003e\n  \u003cli\u003eInstall Keypad.h library from Arduino Library Manager\u003c\/li\u003e\n  \u003cli\u003eDefine 4-row × 3-column key map in sketch\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTypical Applications\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePIN \/ password entry:\u003c\/strong\u003e Security systems, door locks, and access control\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNumeric data entry:\u003c\/strong\u003e Temperature setpoint, timer, and parameter input\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePanel-mount keypad:\u003c\/strong\u003e Adhered to enclosure panel for finished product appearance\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePhone-style input:\u003c\/strong\u003e Familiar telephone layout for user-friendly numeric entry\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003ePackage Contents\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1 × 4×3 membrane keypad with 7-pin ribbon cable connector\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e12-key numeric membrane keypad in standard telephone layout — flexible, adhesive-backed, Arduino Keypad.h compatible for PIN entry and numeric input projects.\u003c\/p\u003e","brand":"Keszoox","offers":[{"title":"Default Title","offer_id":45683768099051,"sku":"","price":4.37,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0677\/1005\/8731\/files\/Membrane-Keypad-4-x-3.jpg?v=1723005004","url":"https:\/\/keszoox.com\/products\/4x3-membrane-keypad-matrix-12-key-numeric-7pin-arduino","provider":"Keszoox","version":"1.0","type":"link"}