Touch Pad Light Kit

Classes 5-6, typical ages 10–12. Age ranges vary by learner. Guided low-voltage electronics.

Activity engagement

40–60 minutes. Explore 5–10 min · Build 10–20 min · Test and discuss 25–30 min. Estimated time for building, testing and discussion.

What you need

No computer required. An adult helps inspect connections.

Included components

• Small Breadboard / Mini Solderless Board - 400 points — 1 breadboard
• Jumper Wire Combo - Male to Male, Male to Female and Female to Female Breadboard Connecting Wires (10 Qty Each) — 1 set
• Illustrated Activity Guide and Observation Sheets — 1 set
• Fitted Headers and Labelled Connection Leads — 1 set
• 4 CELL AA BATTERY HOLDER WITH SWITCH / COVER — 1 holder
• AA BATTERY — 4 battery (individual units)
• Regulated 5 V Power Supply with Short-Circuit Protection — 1 power supply
• TTP223 Capacitive Touch Module — 1 sensor module
• 5mm LED - Red Color — 1 LED
• 1K Ω 1/4 Watts (10 PCS) — 1 resistor

What you learn

• Touch can be detected through a change in capacitance.
• A digital output has two logic states.
• The LED still needs its own current-limiting resistor.

Connection guide

• TTP223 VCC → regulated +5 V; GND → GND; OUT → 1 kOhm → LED anode.
• LED cathode → GND. Use the touch pad only; do not bridge supply terminals.

Steps to make it

1. Disconnect all power and identify the supplied part labels and pinouts before wiring.
2. Leave the module in its supplied momentary active-high configuration; identify VCC, GND and OUT.
3. Wire the sensor and the 1 kOhm LED branch with the supply off.
4. Power on without touching the pad for two seconds to let the sensor settle.
5. Touch and release with a dry finger; then try through one thin dry paper sheet.
6. Repeat the same test ten times and turn the supply off.

Test challenge

Compare touch detection with a bare pad and with a thin insulating sheet.

Observation task

Surface, number of touches, successful detections and false triggers.

Expected result

Touch normally raises OUT and lights the LED; the thin-sheet response depends on thickness and contact.

If it does not work

Check the supplied module mode and keep the pad dry. Allow settling after power-up and use the specified 1 kOhm resistor.

Try next

Explain why capacitive sensing can sometimes work through an insulating cover.

Use and supervision

Use only the supplied low-voltage DC parts. Disconnect power before rewiring; check polarity and labelled pinouts. No soldering or exposed mains connections. Adult guidance is recommended.

How this experiment works

Download class activity guide

Cover illustrations show component types. Functional animations explain principles and are not recorded prototype tests. Follow the supplied connection labels and pinouts.