TC301D Single Channel Capacitance Touch Sensor IC SOP-8

TC301D Single Channel Capacitance Touch Sensor IC SOP-8 delivers a robust, single-button, capacitive sensing solution for modern human-machine interface (HMI) requirements. This specialized IC efficiently converts minute changes in electrode capacitance—caused by a human touch—into a clear digital output signal. Consequently, it enables designers to replace unreliable mechanical switches with sleek, durable, and sealed touch pads, significantly enhancing product longevity and aesthetic appeal. The TC301D integrates all necessary control logic, thus offering automatic calibration and high noise immunity directly on the chip, which minimizes external component count and simplifies your PCB layout. Furthermore, its low-power operation and wide voltage range make it an ideal, cost-effective choice for battery-powered consumer electronics and sealed industrial control panels.

Key Features:

• Single-Channel Sensing: The device controls one fully independent touch sensing key, providing a simple yet reliable input function.
• Automatic Calibration: Notably, the TC301D features auto-calibration for life, automatically correcting for slow environmental changes (like humidity or dust buildup) without requiring manual adjustments.
• High Noise Immunity: An embedded noise immunity circuit provides robust operation, ensuring stable performance even in electrically noisy environments.
• Wide Operating Voltage: It operates reliably across a supply voltage range of 2.5 V to 6.5 V, accommodating various system power requirements.
• CMOS/TTL Output: The OUT pin provides a direct digital signal (High or Low), which you can easily interface with microcontrollers or simple logic circuits.

Technical Specifications:

• Supply Voltage Range (V_CC): 2.5 V to 6.5 V
• Standby Current: Typically 70 μA
• Operating Current: Typically 810 μA
• ESD Protection Voltage: 8 kV (Human Body Model)
• Output Type: Digital Output (Active Low or High depending on configuration)
• Operating Temperature Range: −40°C to +85°C

Mechanical Specifications:

• Package Type: SOP-8 (Small Outline Package, 8-Pin)
• Mounting: Surface Mount Technology (SMT)
• RoHS Compliance: This component is fully RoHS compliant.
• Simplicity: You require minimal external components for proper operation, simplifying the overall design process.

Dimensions:

• Package Type: SOP-8 standard dimensions (≈ 4.9 mm x 3.9 mm body)
• Pin Pitch: ≈ 1.27 mm (0.05 inch)
• PCB Footprint: Designed for standard SO-8 SMT pads.

Pinout and Wiring:

• Pin 1 (SEN): Connect this pin directly to the sensing electrode (touch pad). You should minimize the trace length.
• Pin 2 (CP): Connect to a required external capacitor (C_P) for power-on calibration stability.
• Pin 3 (VREG): Connect to an external decoupling capacitor (C_VREG) for the internal voltage regulator.
• Pin 4 (CSEN): Connect to an external sensitivity setting capacitor (C_SEN). The value determines sensor sensitivity.
• Pin 5 (GND): Connect to the circuit ground (0 V).
• Pin 6 (OUT): This is the digital key output port. It pulls low when touch is detected (typical setup).
• Pin 7 (FUN): Function selection pin. Connect to VCC or GND to select different operation modes/sensitivities.
• Pin 8 (VCC): Connect to the positive power supply (2.5 V to 6.5 V).

Datasheet Reference:

• Download TC301D Capacitive Touch Sensor Datasheet

Commonly Used in:

• Home Appliances: Providing sleek, easy-to-clean touch controls on stoves, washing machines, and small appliances.
• Consumer Electronics: Integrated into media players, portable devices, and user interface keypads.
• Sealed Control Panels: Specifically, the design allows creation of durable, moisture-resistant panels for industrial or outdoor use.

Applications:

• Mechanical Switch Replacement: Use this IC to transition from traditional push-buttons to modern capacitive touch buttons.
• Liquid Level Detection: For example, designers utilize the TC301D to detect the presence or absence of water or other liquids through a non-conductive container wall.
• Keypads and Access Systems: Implementing robust, tamper-resistant key input areas.

Equivalent Models:

• TTP223: A very common single-channel capacitive sensor, often used as a functional replacement in simple applications.
• AT42QT1010: Microchip’s single-channel touch sensor, providing comparable functionality and a digital output.
• TC301F: A related NUTECH part number in the same series, offering a similar touch sensing core.

Package Includes:

• 1 x TC301D Single Channel Capacitance Touch Sensor IC (SOP-8)