TTP223 Touch Switch Module

Replace fiddly mechanical buttons with a clean touch surface. The TTP223 capacitive touch switch module detects the touch of a finger through almost any thin, non-conductive surface, such as wood, acrylic, plastic, or glass, and gives you a crisp digital output you can wire straight into an Arduino, ESP32, Raspberry Pi, or any 2V to 5.5V logic circuit. No moving parts, no contact bounce, no mechanical wear.

Why you'll reach for it

• Single-channel touch detection: a stable, self-locking or momentary replacement for a traditional push button, with consistent touch detection on a human finger.
• Tune it to your project: adjust sensitivity with an external capacitance from 0 to 50pF, from a light tap on bare pad to a firm press through a thicker panel.
• Choose your behaviour with jumper pads: select Fast mode or Low Power mode (LPMB pad), momentary or toggle output (TOG pad), active high or active low output (AHLB pad), and a maximum 100-second on time (MOTB pad).
• Flexible output: Q pin gives a CMOS output, and in open drain mode (bonding option) the OPDO pin is open drain, so it fits a wide range of circuits.

Working with it

Power it from 2V to 5.5V DC and it comes up in about 0.5 seconds. During that stable-time the keypad is disabled, so don't touch it right after power-on. After that, auto calibration handles the rest: the module re-calibrates about every 4 seconds while the key has not been touched, so the sensing point stays accurate over time. There is also an external power-on reset pin (RST) if you want control over the reset behaviour.

Specifications

• Board dimensions: 15mm x 11mm
• Input voltage: 2V to 5.5V DC
• Response time: max ~60ms in Fast mode, ~220ms in Low Power mode at VDD = 3V
• Sensitivity adjustment: external capacitance, 0 to 50pF
• Two sampling length options via the SLRFTB pad
• Maximum on time: 100 seconds, settable via the MOTB pad
• External power-on reset pin (RST)
• Auto calibration with ~4.0 second re-calibration period when the key is untouched

Good fits for this module

• Touch-activated switches for panels, enclosures, and furniture lighting
• Touch inputs for microcontroller projects where mechanical buttons fail or wear out
• Interactive installations, exhibits, and student projects that need a sealed, wipeable control surface

A small board that quietly makes a project feel finished: your finger lands, the light comes on, and there is nothing to click.