D1(ESP-12E) WiFi Development Board

SmartElex PCA9546 4-Channel I2C Multiplexer Compatible with TCA9546A SmartElex PCA9546 4-Channel I2C Multiplexer is designed to simplify communication management when working with multiple I2C devices that share the same address. This compact module helps prevent signal conflicts by allowing users to connect and control up to four separate I2C buses from a single master device. It’s an ideal solution for students, makers, engineers, educators, and startups who are building projects where multiple sensors or modules need to coexist without addressing limitations or communication errors. Compatible with popular development platforms like Arduino, Raspberry Pi, and ESP32, this PCA9546 I2C multiplexer works as a practical I2C bus expander for robotics, IoT systems, automation projects, and prototype development. It offers a stable, plug-and-play approach to expanding I2C networks, making it easy to integrate sensors, displays, and controllers into both simple and advanced builds. Whether you are creating a multi-sensor environment, debugging complex circuits, or scaling an existing project, this module provides clear routing and dependable performance to streamline development. Features: Enables connection of up to four independent I2C device channels Prevents address conflicts by isolating I2C buses when needed Based on PCA9546 IC and compatible with TCA9546A devices Ideal for expanding I2C networks in multi-sensor projects Works with Arduino, Raspberry Pi, ESP32, and similar controllers Simple control through I2C commands for channel selection

7Semi MCP23017 I2C to 16 IO Expander Breakout Board The 7Semi MCP23017 I2C to 16 IO Expander Breakout Board is designed to expand the digital I/O capability of microcontrollers using the trusted MCP23017 I2C IO Expander IC. It provides exactly 16 configurable GPIO pins over a single I2C bus, reducing wiring complexity while maintaining stable performance. Each pin can be independently set as input or output, and the onboard interrupt feature allows the controller to respond instantly to pin state changes. This MCP23017 Breakout Board is compact, easy to integrate, and ideal for applications such as home automation, robotics, industrial control panels, and any project that requires multiple digital inputs and outputs without consuming extra microcontroller pins. Features: 16 I/O Pins: Converts two signal pins into sixteen completely customizable I/O pins. Multi-board Expansion: For larger applications, stack up to 8 boards to provide up to 128 I/O pins. Configure I2C addresses by setting the A0, A1, and A2 jumpers. Dual Connectivity: Includes PH2.0 terminal and solder pad choices for simple connection. Wide Compatibility: Compatible with both 3.3V and 5V systems, ensuring platform versatility. Interrupt Support: The INTA and INTB interrupt pins are used for real-time signal handling. Development Resources: Includes detailed instructions and sample projects for Raspberry Pi, Arduino, STM32, and micro. Easy Integration: The I2C interface, combined with a 4Pin 2.0 mm JST connector, provides for an easy and flexible connection to any MCU.

SCD40 I2C CO Temperature & Humidity Sensor Breakout Module - 7Semi The 7Semi SCD40 is a compact sensor breakout based on Sensirion’s advanced photoacoustic NDIR technology. It accurately measures CO concentration from 400 ppm to 40,000 ppm, along with ambient temperature and humidity. Ideal for air quality monitoring, HVAC systems, and IoT applications. It communicates over the I²C interface and is compatible with most microcontrollers. With low power consumption, long-term stability, and minimal recalibration requirements, the SCD40 is well-suited for portable and embedded systems requiring reliable environmental data. Features Photoacoustic CO Sensing: Uses advanced photoacoustic infrared technology for high-precision CO measurement. 3-in-1 Environmental Monitoring: Simultaneously tracks CO levels, temperature, and humidity for a complete atmospheric overview. Wide CO Detection Range: Measures concentrations from 400 ppm to 40,000 ppm, with optimal accuracy in the 400–2000 ppm range. High Accuracy: Offers a precision of ±(40 ppm + 5%), making it ideal for critical monitoring applications. Low Power Consumption: Consumes only 17 mA at 5s intervals and 0.5 mA at 5-minute intervals, perfect for battery-powered projects. Plug-and-Play Ready: Factory-calibrated and ready for immediate use—no manual calibration required. I2C Interface: Compatible with Arduino, Raspberry Pi, ESP32, STM32, and other popular microcontrollers via I2C. Compact Design: Small, robust module fits easily into embedded systems and space-limited enclosures. SCD40 carbon dioxide sensor Breakout I2C Arduino Connections

Cytron Maker UNO Plus – Arduino-Compatible Educational Board The Cytron Maker UNO Plus is a beginner-friendly, Arduino-compatible development board designed to simplify electronics and coding for students, educators, and STEM hobbyists. With onboard LEDs, a built-in piezo buzzer, a programmable pushbutton, and upgraded components, this board removes wiring complexity allowing learners to focus on coding, debugging, and hands-on exploration. Whether used for school projects, robotics, or microcontroller education, the Cytron Maker UNO Plus ensures a smooth and frustration-free learning experience. Thanks to its pre-labeled pin headers, Micro USB connectivity, and fully Arduino-compatible architecture, setup becomes effortless for new users. Students can instantly code and visualize real-time pin activity through indicator LEDs, making debugging easier and more intuitive. The Cytron Maker UNO Plus is ideal for classroom teaching, STEM labs, maker workshops, and hobby projects, helping learners jump straight into creating fun electronics projects like light sequences, melodies, and interactive displays. Features: Fully compatible with Arduino ecosystem, sharing all libraries and example codes. Integrated 12× onboard LEDs for simplified debugging and visual learning. Built-in piezo buzzer and programmable pushbutton for interactive projects without extra wiring. Upgraded 3.3V line provides 500mA output to support more sensors and modules. Micro USB interface replaces bulky USB Type-B for universal connectivity. Uses FT231X USB-to-Serial converter for easier and more reliable driver installation. Includes pin-header label stickers for effortless classroom identification. CE, FCC & RoHS compliant - safe, environmentally friendly, and education-ready. Students can write their names directly on the board to avoid mix-ups.

Cytron Maker Uno RP2040 Development Board The Cytron Maker Uno RP2040 Development Board combines the familiar Arduino Uno form factor with the powerful Raspberry Pi RP2040 dual-core processor, making it an ideal choice for students, hobbyists, and makers. With 264KB internal RAM, 2MB onboard flash, and support for Arduino IDE, MicroPython, and CircuitPython, it delivers the perfect balance of performance and ease of learning. Whether you're building robotics projects, automation systems, or STEM learning modules, the Maker Uno RP2040 provides a smooth development experience with plug-and-play convenience. Designed for effortless prototyping, the Cytron Maker Uno RP2040 comes with Grove ports, Maker ports, onboard LEDs, user buttons, a programmable buzzer, RGB LEDs, and dedicated servo ports for connecting multiple actuators with zero wiring hassle. The board supports USB-C or LiPo battery power, complete with built-in charging and safety circuitry. From classroom teaching to rapid prototyping and hobby projects, the Cytron Maker Uno RP2040 Development Board ensures hands-on creativity with reliable performance and simplicity. Features: Powered by Raspberry Pi RP2040 dual-core Arm Cortex-M0+ processor Arduino/Maker Uno form factor for broad project compatibility Supports Arduino IDE, MicroPython, and CircuitPython Includes 6 Grove ports, 1 Maker port, and 4 dedicated servo ports Equipped with 16 GPIO status LEDs, RGB LEDs, piezo buzzer, reset/user/boot buttons Dual power options: USB-C or single-cell LiPo battery Built-in LiPo charging circuit with overcharge and discharge protection Ideal for coding education, robotics, IoT, and STEM learning Pinout Diagram:

SmartElex 12V 20A Single Channel Power Relay Module The SmartElex 12V 20A Single Channel Power Relay Module is a high-current switching solution designed to control heavy electrical loads using low-voltage control signals. It helps safely operate high-power devices without directly exposing microcontrollers or control circuits to high current, reducing risk and improving system reliability. This module is suitable for students, makers, engineers, educators, and startups who are working on power control, automation, or embedded electronics projects that demand robust switching capability. This single channel power relay module is ideal for robotics, IoT systems, home and industrial automation, and power management applications where devices such as motors, heaters, pumps, or high-load appliances need reliable control. It can be easily interfaced with popular platforms like Arduino, Raspberry Pi, and ESP32, making it convenient for both prototyping and deployment. The strong build quality and straightforward integration make it a dependable choice for projects requiring consistent and safe high-current switching. Features: Single channel power relay module for high-current load control Operates on 12V, suitable for industrial and automation systems Supports heavy load switching up to 20A Electrical isolation between control and power circuits for safety Compatible with Arduino, Raspberry Pi, ESP32, and similar controllers Robust design for reliable operation in power control applications

SmartElex RLS05 Line Follower Sensor The SmartElex RLS05 Line Follower Sensor is a compact and easy-to-use module designed to help robots detect and follow lines on a surface with accuracy. It is ideal for students, makers, educators, and early-stage engineers who are learning robotics or building simple autonomous systems. The sensor simplifies line detection by clearly identifying path contrasts, making it easier to develop reliable line-following behavior without complex circuit design. This sensor is widely used in line follower robots, educational robotics kits, and automation prototypes where precise path tracking is required. It integrates smoothly with popular platforms such as Arduino, Raspberry Pi, and ESP32, allowing quick setup and experimentation. With dependable performance and straightforward interfacing, the SmartElex RLS05 enables users to focus on coding logic and robot movement, making it well suited for classrooms, labs, competitions, and DIY robotics projects in India. Pin Diagram: How to Calibrate SmartElex RLS05 Line Follower Sensor Step 1: Enter Calibration Mode Press the calibration button once or pull the CAL pin low for a few milliseconds. When three LEDs (D0, D2, and D4) turn ON, the module has entered calibration mode. Step 2: White Surface Reading Place the RLS05 module on a white surface and press the calibration button again. When two LEDs (D3 and D4) turn ON, the white surface values are read and saved in EEPROM. Step 3: Black Surface Reading Place the module on a black surface and press the calibration button once more. When three LEDs (D2, D3, and D4) turn ON, the black surface values are read and stored. Step 4: Select Line Following Mode To enable white line following, press the calibration button three times within one second. LEDs (D2, D3, and D4) will blink to confirm selection. To enable black line following, press the calibration button twice. LEDs (D0, D1, and D2) will blink to confirm the mode selection. Features: Five-channel line detection for accurate and stable line following Supports both black line and white line tracking modes One-time calibration with onboard EEPROM memory Easy calibration using onboard push button or CAL pin Compatible with Arduino, Raspberry Pi, and ESP32 platforms Ideal for robotics projects, educational kits, and automation prototypes

7Semi MAX31855 K-Type Thermocouple Amplifier Breakout The 7Semi MAX31855 Thermocouple Amplifier Breakout is designed for creators, engineers, and industrial users who need reliable and highly accurate temperature readings from extreme environments. With its advanced MAX31855 converter IC, this breakout allows effortless digital temperature measurement using K-type thermocouples, making it a powerful choice for applications like 3D printing, HVAC monitoring, and high-heat industrial systems. The onboard cold-junction compensation ensures precision by automatically correcting any thermal offsets at the connector. Supporting temperatures from -270°C to +1372°C, it delivers 14-bit resolution with smooth 0.25°C read steps, providing dependable, noise-free readings for sensitive processes. Built-in fault detection helps identify open circuits or shorts, making the system easier to troubleshoot and safer for continuous operation. With its SPI-based digital interface and compatibility with 3.3V/5V logic microcontrollers, the module integrates cleanly with Arduino, ESP32, Raspberry Pi, and industrial controllers. Features: Supports a wide thermocouple measurement range from –270°C to +1372°C, making it suitable for extreme heat and cryogenic applications. Provides 14-bit high-resolution output with precise 0.25°C increments for accurate temperature monitoring. Includes built-in cold-junction compensation, ensuring reliable compensation for ambient temperature fluctuations. Offers a simple SPI digital interface, requiring minimal I/O pins for easy integration with most microcontrollers. Compatible with multiple thermocouple types including K, J, N, T, S, R, and E, providing versatility in system design. Features fault detection for open thermocouples and shorts to VCC/GND to enhance system safety. Supports both 3.3V and 5V logic levels, ensuring broad compatibility across development boards.

SmartElex Sound Detection Sensor The SmartElex Sound Detection Sensor is a compact and efficient sound sensor module designed to detect sound presence and measure sound intensity with precision. Built around the LM386 audio amplifier, it provides both analog (AOUT) and digital (DOUT) outputs, making it suitable for a wide range of applications—from simple sound-triggered actions to detailed audio level monitoring. Operating smoothly between 3.3V and 5.3V, this sound sensor Arduino compatible module integrates easily with popular development boards such as Arduino, STM32, and Raspberry Pi. Its low power consumption, small form factor, and included 4-pin cable make it perfect for sound-activated projects, noise detection systems, smart devices, and interactive electronics where reliable audio sensing is required. Features: LM386 audio amplifier for a powerful sound signal enhancement. Detect low-level sounds with 200× amplification. Wide voltage range: 3.3 to 5.3 volts Dual outputs: analog (AOUT) and digital (DOUT). Low power consumption, suitable for embedded systems. Adjustable gain using external components Compact and lightweight; breadboard-friendly. Simple integration with Arduino, STM32, and more.

Waveshare 3.5inch Capacitive Touch LCD IPS Display Module 320×480 The Waveshare 3.5-inch Capacitive Touch LCD IPS Display Module is a compact yet powerful display solution featuring a 320 × 480 pixel resolution that delivers crisp visuals and excellent clarity. Designed with an IPS panel, it offers wide viewing angles and consistent color performance, making it ideal for graphical interfaces and interactive applications. The module integrates the ST7796S display driver for reliable display control and the FT6336U capacitive touch controller for accurate, multi-touch responsiveness. Optimized for embedded development, this 3.5 inch LCD Raspberry Pi display is perfectly suited for Raspberry Pi projects, control panels, and custom HMI applications where space, touch precision, and visual quality matter. Features: 320×480 resolution, 262K colors, clear and colorful displaying effect High touch screen transmittance, fast response and long lifetime Embedded with ST7796S driver chip and FT6336U capacitive touch control chip, using SPI and I2C communication respectively, minimizes required IO pins Onboard TF card slot for storing more pictures, videos, music, etc. Adapting 15PIN connector and 18PIN FPC slot for connecting the LCD module to the host board Onboard voltage translator, compatible with 3.3V / 5V operating voltage Comes with online development resources and manual (examples for Raspberry Pi / ESP32 / Raspberry Pi Pico / Arduino) SPI and I2C Control Interfaces: Pin Description 15PIN Pin No. 18PIN Pin No. VCC Power (3.3V / 5V input) 1 1 3V3 Power (3.3V input) 2 NC GND Ground 3 3 MISO SPI MISO pin 4 6 MOSI SPI MOSI pin 5 5 SCLK SPI CLK pin 6 4 SD_CS TF card chip selection, low active 7 10 LCD_CS LCD chip selection, low active 8 9 LCD_DC LCD data/command selection (high for data, low for command) 9 7 LCD_RST LCD reset pin, low active 10 8 LCD_BL LCD backlight pin 11 2 TP_SDA Touch panel data pin 12 14 TP_SCL Touch panel clock pin 13 13 TP_INT Touch panel interrupt pin 14 15 TP_RST Touch panel reset pin, low active 15 12

SmartElex 5V 3A 4 Channel Signal Relay Module The SmartElex 5V 3A 4 Channel Signal Relay Module is a compact and reliable 4 Channel Relay Module designed to control four independent medium-power loads with precision. Powered as a 5V relay module, it integrates high-quality JY4100F-S-DC5V-C relays, each capable of switching up to 3A at 120V AC or 24V DC. With dedicated trigger inputs and LED status indicators for every channel, it allows easy monitoring and accurate switching. This module directly interfaces with popular microcontrollers such as Arduino, ESP8266, and Raspberry Pi, making it ideal for IoT, home automation, and embedded control applications where safety, isolation, and consistent performance are essential. Applications: Home automation (controlled lights, fans, and locks) Industrial machine control IoT multi-device projects. Robotics and Motor Control Security systems and alarms. Cautions: Always utilize a properly regulated 5V power supply. Avoid exceeding the rated load capacity. Provide proper isolation for AC loads. Store the module in a dry, clean place. Features: Four-channel relay module allows for independent control of four devices. Operates at 5V DC and has an active LOW/HIGH trigger. Each relay can handle up to 3A at 120V AC or 24V DC. Compatible with Arduino, ESP8266, Raspberry Pi, and more platforms. Each channel has its own set of LED indicators. Fast switching: ≤10 ms operation and ≤5 ms release time. Low contact resistance (≤100 mΩ) ensures effective operation. The total power consumption is around 1.44W over four channels. High insulation resistance and dielectric strength are essential for safety. Wide operational temperature range (-40°C to +85°C).

SmartElex ILD213T Opto-isolator Breakout Board SmartElex ILD213T Opto-isolator Breakout Board is designed to provide reliable electrical isolation between two circuits, helping protect sensitive components from voltage spikes, noise, and ground loop issues. This opto isolator board uses the ILD213T optocoupler to safely transfer signals while keeping high-voltage and low-voltage sections separated. It is a practical solution for students, hobbyists, engineers, educators, and startups who need to interface microcontrollers with external hardware without risking damage to their development boards or sensors. This ILD213T optoisolator module is well-suited for robotics, IoT systems, industrial automation, and embedded prototyping where signal integrity and safety are important. It integrates easily with platforms like Arduino, Raspberry Pi, and ESP32, enabling secure communication with relays, motors, sensors, and noisy electrical equipment. By using this electrical isolation board, users can build more stable and durable projects, ensuring consistent performance and reduced troubleshooting due to interference or short circuits. Features: Provides electrical isolation between input and output circuits Based on the ILD213T optocoupler for reliable signal transfer Protects microcontrollers from voltage spikes and noise Helps prevent ground loops and interference issues Compatible with Arduino, Raspberry Pi, ESP32, and similar boards Ideal for robotics, IoT, automation, and industrial interfaces

ACEBOTT QE201 Wooden Board for ESP32 Basic Starter Kit (Expansion Pack) The ACEBOTT QE201 Wooden Board for ESP32 Basic Starter Kit (Expansion Pack) is a practical learning expansion designed to enhance the core ESP32 starter kit with real-world, hands-on projects. Built with wooden structural assembly support, this expansion enables users to create 37+ interactive projects such as a Smart Butterfly, Electronic Piano, Smart Watermelon Fan, Smart Barrier, and Smart Trash Can. It is fully compatible with Arduino and Blockly programming, making it ideal for beginners who want to learn electronics, coding, and automation in a simple and humanized way. The main core function of this expansion pack is to transform basic electronic concepts into physical smart models, helping users understand how embedded systems work through engaging and easy-to-build projects. Features: Supports 37+ practical expansion projects for ESP32 learning Designed for wooden structural assembly to build physical smart models Compatible with ACEBOTT QE201 ESP32 Basic Starter Kit Works with both Arduino and Blockly programming platforms Includes smart applications like Smart Butterfly, Electronic Piano, Smart Fan, Smart Barrier, Smart Trash Can Beginner-friendly design for easy assembly and understanding Humanized learning approach for interactive STEM education Suitable for students, hobbyists, and training institutes

SmartElex 12V 3A 8 Channel Signal Relay Module The SmartElex 12V 3A 8 Channel Signal Relay Module is a reliable control solution designed to switch multiple electrical devices using low-power control signals. It allows users to safely manage higher-voltage or higher-current loads without directly connecting them to sensitive control circuits. This module is suitable for students, makers, engineers, educators, and startups working on embedded systems, automation projects, and control applications that require dependable multi-channel switching. This 8-channel relay module is ideal for robotics, IoT systems, home and industrial automation, and advanced prototyping where several devices need to be controlled independently. It can be easily interfaced with popular platforms such as Arduino, Raspberry Pi, and ESP32 to control lights, motors, pumps, relays, or other external equipment. The straightforward design and consistent performance make it easy to integrate into both experimental setups and finished products, supporting safe and efficient control across a wide range of applications. Features: 8-channel relay module for controlling multiple devices independently Operates on 12V, suitable for automation and control systems Supports up to 3A load current per relay channel Electrical isolation between control signals and load circuits Compatible with Arduino, Raspberry Pi, ESP32, and other controllers Compact board design with LED indicators for channel status

SmartElex LHI778 PIR Motion Sensor Module The SmartElex LHI778 PIR Motion Sensor Module is a passive infrared motion detection solution designed to sense human movement by detecting changes in infrared radiation. It helps solve the problem of automatic motion detection without continuous monitoring, making systems more energy efficient and responsive. This module is suitable for students, makers, engineers, educators, and startups working on electronics projects that require reliable motion sensing for control, security, or automation purposes. This PIR motion sensor module is widely used in robotics, IoT devices, security systems, and home or industrial automation projects where movement detection is required. It can be easily interfaced with popular development platforms such as Arduino, Raspberry Pi, and ESP32, allowing quick integration into prototypes and functional systems. The simple interface and consistent performance make it ideal for applications like motion-activated lighting, intrusion detection, smart alarms, and interactive electronic projects. Features: Passive infrared (PIR) sensor for reliable human motion detection Detects movement by sensing changes in infrared radiation Low power operation suitable for battery-powered projects Digital output for easy interfacing with microcontrollers Compatible with Arduino, Raspberry Pi, ESP32, and similar boards Ideal for security systems, automation, and motion-activated applications