4 x 4 / 4 x 3 Matrix Black Keypad keyboard

Specifications

• Type: Matrix keypad
• Layout Options:
  • 4×4 (16 keys arranged in a 4-row by 4-column matrix)
  • 4×3 (12 keys arranged in a 4-row by 3-column matrix)
• Key Style: Tactile membrane buttons
• Key Color: Black
• Key Labeling: Standard alphanumeric (0-9), *, # for 4×3 layout; additional A, B, C, D for 4×4 layout.

Electrical Specifications:

• Operating Voltage: Typically 5V DC (compatible with 3.3V for microcontrollers such as Arduino, Raspberry Pi)
• Current Rating: <10mA
• Switch Type: Membrane switch
• Contact Resistance: ≤100Ω
• Insulation Resistance: ≥100MΩ (at 250V DC)
• Dielectric Strength: 250V AC for 1 minute
• Bounce Time: ≤5ms
• Lifespan: >1 million key presses

Mechanical Specifications:

• Dimensions (4×4 Matrix Keypad):
  • Keypad Size (L x W): Approx. 69mm x 69mm
  • Key Size: Approx. 12mm x 12mm per key
• Dimensions (4×3 Matrix Keypad):
  • Keypad Size (L x W): Approx. 70mm x 77mm
  • Key Size: Approx. 12mm x 12mm per key
• Thickness: Typically 1.8mm to 2mm
• Material:
  • Front Layer: Polyester (PET) or Polycarbonate (PC)
  • Back Layer: Adhesive backing for easy attachment
• Connector Type:
  • Flat ribbon cable with female header pins or pin header (for direct connection to microcontrollers)
  • Number of Pins:
    • 7 pins for 4×3 layout
    • 8 pins for 4×4 layout

Keypad Matrix Configuration:

• 4×3 Layout:
  • Rows: 4 (R1, R2, R3, R4)
  • Columns: 3 (C1, C2, C3)
  • Number of Keys: 12 (0-9, *, #)
• 4×4 Layout:
  • Rows: 4 (R1, R2, R3, R4)
  • Columns: 4 (C1, C2, C3, C4)
  • Number of Keys: 16 (0-9, A, B, C, D, *, #)

Interface and Compatibility:

• Interfacing: Uses row-column scanning method (matrix scanning) to detect key presses
• Microcontroller Compatibility:
  • Compatible with microcontrollers like Arduino, Raspberry Pi, ESP32, STM32, etc.
  • Can be easily interfaced via GPIO pins using a keypad library for Arduino or custom logic for other platforms
• Signal Output: Keypad outputs binary signals based on key presses via the matrix configuration (rows and columns short when a key is pressed)

Environmental Specifications:

• Operating Temperature Range: -10°C to 50°C
• Storage Temperature Range: -20°C to 60°C
• Operating Humidity: 20% to 90% RH (non-condensing)

Mechanical Features:

• Durability: Designed for long-term use in harsh environments
• Waterproofing: Some models have water-resistant membranes for added durability in industrial environments.
• Key Feedback: Soft tactile feedback (depending on membrane type)

Mounting:

• Installation: Typically uses adhesive backing for mounting on flat surfaces. Screw mounts or other mechanical fastening options can be used depending on the enclosure design.