Search components by part name, signal type, voltage notes, and common mistakes.
A 4-digit 7-segment display combines four numeric displays and relies on fast multiplexing so the eye sees all digits at once.
Each segment path needs current limiting. Multiplexed displays can still draw meaningful total current.
A 4x4 keypad is a matrix of 16 buttons arranged as four rows and four columns.
Passive switch matrix. Use 3.3V-safe GPIO scanning with pull-up or pull-down inputs.
A 7-segment display uses seven LED segments, plus often a decimal point, to form digits and a few letters.
Common cathode display in this kit. Each segment is an LED and needs current limiting.
The 74HC595 is an 8-bit serial-in, parallel-out shift register with a storage register and tri-state outputs. It lets a Pico control more output pins while using only a few GPIO signals.
Use a logic supply compatible with the circuit. With Pico projects, keep the logic side 3.3V-safe unless a level-shifting design is intentionally used.
A KY-035 analog Hall magnetic sensor outputs a changing voltage as magnetic field strength changes.
Use module power that keeps the analog output inside Pico ADC limits.
A solderless breadboard is a reusable prototyping board. The holes are not all separate: hidden metal strips connect groups of holes so parts and wires can share the same electrical node.
Passive part. It carries whatever low-voltage rails and signals you wire into it.
A button is a momentary switch: it changes a circuit only while someone is pressing it.
Passive switch. Wire it as a 3.3V-safe digital input with a pull-up or pull-down path.
A buzzer is an audio signaling component that turns electrical control into sound.
DC-powered buzzer. Passive buzzers need a square wave, and SunFounder notes a typical passive-buzzer drive frequency range of 2 kHz to 5 kHz.
A capacitor stores electric charge. In circuits it is used for smoothing, filtering, timing, coupling, and short-term energy storage.
Passive part. Choose capacitance, voltage rating, and polarity/type for the circuit.
A DC motor converts electrical energy into continuous rotation.
SunFounder identifies this as a 3V DC motor with 1-6V operation range, 70mA free-run current at 3V, 13000RPM free-run speed at 3V, 800mA stall current at 3V, and 2mm shaft diameter.
A small submersible DC pump that moves water from its inlet through an outlet tube.
SunFounder lists DC 3-4.5V, 120-180mA operating current, 0.36-0.91W power, 0.35-0.55m max water head, and 80-100 L/H max flow rate.
The DHT11 is a digital temperature and humidity sensor module. It reports relative humidity and temperature over a single DATA line using a timing-based 40-bit message.
SunFounder lists working voltage as DC 5V. Confirm module output behavior before direct Pico GPIO connection; for beginner Pico builds, prefer a 3.3V-safe module supply/data path when supported.
A KY-001 temperature module uses a DS18B20 digital temperature sensor with a one-wire style data bus.
Use Pico-safe data pull-up voltage and module supply wiring.
A KY-028 digital temperature module uses a thermistor plus comparator so code can read both analog temperature trend and threshold state.
Use module power and output levels that are safe for Pico GPIO.
A diode is a two-terminal semiconductor part that conducts much more easily in one direction than the other.
Passive semiconductor. Select current, voltage, and diode type for the job.
A KY-039 heartbeat module uses an infrared emitter and light sensor to detect changes as blood flow changes in a fingertip.
Use module power that keeps the signal output inside Pico ADC limits.
A KY-026 flame sensor module detects infrared light commonly produced by flames.
Use module power and AO/DO levels that are safe for Pico.
A KY-003 Hall magnetic sensor module switches its digital output when the right magnetic field is nearby.
Use module power and output levels that are safe for Pico GPIO.
A KY-037 microphone module senses sound level with both an analog output and an adjustable digital threshold output.
Use module power that keeps AO/DO outputs Pico-safe.
An LCD1602 is a 16-column by 2-row character display. The I2C backpack reduces the many LCD parallel pins to four useful module pins.
SunFounder labels VCC as 5V. Confirm the I2C pull-up behavior before connecting to Pico GPIO.
An infrared obstacle avoidance module sends IR light and watches for a reflection from nearby objects.
KY-032 boards are commonly powered as modules; verify VCC and output voltage before Pico wiring.
An infrared receiver detects modulated IR light from a remote control and outputs a digital signal that a microcontroller can decode.
SunFounder lists the HX1838 IR receiver sensor power supply as 3.3-5V. Pico projects should use 3.3V-side signal wiring.
A KY-005 infrared transmitter module emits invisible infrared light, usually for remote-control style signals.
KY-005 modules usually use VCC, GND, and a digital signal input. Confirm the module voltage before wiring.
A joystick module turns stick movement into two analog positions and usually adds a digital press switch under the stick.
Use 3.3V for Pico ADC projects so the X and Y outputs stay inside the GPIO-safe range.
Jumper wires are short reusable wires with connector ends for moving signals and power between the Pico, breadboard, and modules.
Passive wire. It carries the voltage or signal you connect to it.
A KY-031 knock sensor module detects tap or shock events with a contact-style vibration element.
Passive/digital tap sensor module. Use Pico-safe pull-up or pull-down wiring.
An LED is a light-emitting diode: a directional semiconductor part that turns electrical energy into visible light.
Use a current-limiting resistor in series. SunFounder notes typical red/yellow/green forward voltage around 1.8V, white around 2.6V, and common LED current up to 20mA.
An LED bar graph is a row of individual LEDs in one package, useful for showing levels such as progress, volume, signal strength, or sensor value.
Each LED segment needs current limiting. Current planning matters if many segments are on at once.
An LED dot matrix is a grid of LEDs arranged in rows and columns for simple icons, patterns, letters, and animations.
The kit uses a CA dot matrix labeled 788BS. Current limiting and scan timing are required.
A KY-008 laser transmitter module emits a small red laser dot when its signal input is enabled.
Typical KY-008 laser modules are low-current digital output modules. Verify board label voltage before connecting to Pico.
A small module that lets a Pico project charge and run from a single-cell Li-po battery when used as SunFounder shows.
Input 5V, output 3.3V per SunFounder. Battery connector is PH2.0.
A KY-010 light blocking module uses a slot-style photo interrupter to detect when something blocks a light beam.
Use module power and signal output that are safe for Pico GPIO.
A KY-033 line tracking module compares reflected infrared light from light and dark surfaces.
Use module power and output levels that are safe for Pico GPIO.
A KY-024 linear Hall module senses magnetic field strength and can provide analog and threshold outputs.
Use module power that keeps AO/DO outputs Pico-safe.
The MFRC522 module reads and writes 13.56 MHz contactless RFID/NFC-style cards and tags.
Use 3.3V module power and 3.3V logic with the Pico. Do not assume a 5V RFID module is GPIO-safe.
The MPR121 module is a capacitive-touch controller that lets the Pico sense touch pads, foil, wires, or other electrodes over I2C.
SunFounder labels the module power pin as 3.3V. The MPR121 datasheet family supports low-voltage operation.
The MPU6050 module is a 6-axis motion sensor with a 3-axis accelerometer and 3-axis gyroscope.
Use Pico-safe module power and I2C logic. Verify the board labels and regulator/level-shift behavior before wiring.
A KY-027 magic light cup module pair combines tilt sensing and light output to mimic pouring light between cups.
Use module wiring that keeps sensor outputs Pico-safe.
A KY-017 mercury tilt switch module changes state when the sealed conductive bead shifts with tilt.
Passive/digital switch module. Use Pico-safe pull-up or pull-down wiring.
A KY-036 metal touch module detects contact with its touch pad and outputs a digital signal.
Use module power and output levels that are safe for Pico GPIO.
A micro switch is a small snap-action switch with an actuator that changes contact state when pressed by an object.
Passive switch. Read it with 3.3V-safe digital input wiring and a pull-up or pull-down path.
A KY-038 sound sensor module uses a microphone and threshold circuit to detect sound events.
Use module power and output levels that are safe for Pico.
A PIR motion sensor detects changes in infrared radiation from warm moving bodies.
Module-powered digital sensor. Verify the module supply and output voltage before connecting the signal pin to Pico GPIO.
A photoresistor, or photocell, is a light-sensitive resistor. Its resistance drops when brighter light hits the sensitive surface.
Passive sensor. Use it in a 3.3V voltage divider with a fixed resistor so the Pico ADC reads a safe changing voltage.
A potentiometer is a three-terminal variable resistor. Turning the knob changes the voltage seen at the middle terminal when it is wired as a divider.
Passive part. For Pico lessons, connect the outer terminals to 3.3V and GND so the wiper stays inside the ADC range.
An RGB LED packages red, green, and blue LEDs together so a circuit can mix colors by controlling each channel.
Common cathode RGB LED. Each color channel needs its own current-limiting resistor.
Raspberry Pi Pico 2 W is the main microcontroller board for ObsoleteHQ. It combines the RP2350 microcontroller, onboard wireless hardware, USB programming, power regulation, and breadboard-friendly GPIO pins.
USB power for beginner lessons. GPIO logic is 3.3V only. Use 3V3/GND rails carefully and do not use GPIO pins as power supplies for loads.
A reed switch is a magnetic-field switch sealed in a glass tube.
Passive switch. Read it as a 3.3V-safe digital input with a pull-up or pull-down.
A relay is an electrically controlled switch that uses a coil and moving contacts to open or close another circuit.
The relay image shows a Songle SRS-05VDC-SL marking with 5V coil family and printed contact ratings of 3A 250VAC / 30VDC. ObsoleteHQ beginner projects keep relay loads low-voltage DC only.
A resistor limits current and sets voltage/current behavior in a circuit. In student projects it often protects LEDs, creates pull-up or pull-down behavior, or forms a voltage divider.
Passive part. Choose a resistance and power rating that fits the circuit.
A KY-040 rotary encoder reports rotation steps and direction with two digital signals, plus a press switch.
Passive/digital encoder module. Use Pico-safe pull-ups or module output wiring.
A hobby servo is a closed-loop positioning actuator: a small motor, gears, potentiometer, and controller board work together to move and hold a shaft angle.
Use appropriate servo power. Do not assume the Pico GPIO can power the servo motor.
A slide switch is a maintained switch: sliding the handle leaves the circuit in one selected state until it is moved again.
Passive switch. Use as a 3.3V-safe digital input or low-current signal selector.
The TA6586 is a monolithic motor-driver IC for bidirectional DC motors. It accepts two logic input signals to control forward, reverse, brake, and stop behavior.
Motor supply depends on the motor circuit. Logic inputs come from Pico GPIO; motor current must not pass through the Pico GPIO pins.
A thermistor is a resistor whose resistance changes strongly with temperature.
Passive sensor. Use it in a 3.3V voltage divider with a fixed resistor before connecting to Pico ADC.
A tilt switch is a simple orientation sensor. In this kit it is a ball-type switch with a metal ball inside.
Passive switch. Read it as a 3.3V-safe digital input with a pull-up or pull-down.
A transistor is a semiconductor part that lets a small control signal influence a larger current path. In beginner Pico projects it is usually used as an electronic switch.
The Pico drives the base through a resistor; the load uses its own suitable supply path.
Two-color LED modules combine red/green LED channels so code can show red, green, yellow-ish blends, and status states.
Each LED color channel needs appropriate current limiting and Pico-safe GPIO current.
The HC-SR04 ultrasonic module measures distance by sending a 40 kHz sound pulse and timing the echo.
SunFounder lists VCC as 5V, working current 16mA, and Echo as a TTL pulse output. Protect Pico GPIO if Echo is 5V.
A KY-002 vibration switch module changes state when movement or shock shakes its internal contact.
Passive/digital switch module. Use Pico-safe pull-up or pull-down wiring.
An 8-pixel strip of individually addressable RGB LEDs. Each LED includes a WS2812B control IC inside the 5050 RGB package.
SunFounder lists DC5V work voltage and 0.3W consumption per LED.
A water level sensor module uses exposed conductive traces to produce a changing signal as more of the probe touches water.
Power only while taking readings when possible. Use Pico-safe voltage and keep electronics away from spills.
