Different Sensors,Actuators and Modules

  1. Temperature Sensor
    A temperature sensor is an electronic device that measures the temperature of its environment and converts the input data into electronic data to record, monitor, or signal temperature changes. There are many different types of temperature sensors.Non-contact temperature sensors are usually infrared sensor. There are different sensors.
    You should check the link here to compare various sensors.


    The DHT11 is a basic, ultra low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analog input pins needed).The picture above shows a DHT11.
  2. Hall effect sensors
    Allegro systems provide various temperature sensors based on hall effect. You may check out their official website here OPAMPS can be used here. Check out the video here to learn how to use them.

    Hall sensor with an opamp

  3. Light sensor
    LDR are popular and cheapest device for light detection. They can be used along with a comparator (the pot sets threshold) to detect brightness after a certain prespecified level. They can even provide a rough lux data. Resistance of LDR varies inversely with light. THe graph is a hyperbolic one. Below image shows one of such sensors.
    LDR sensor with an opamp

  4. Smoke sensor
    smoke sensors are available in cheap. most cheapest one is the MQ series sensor. Click below to see different versions of it.

    Click on the image here to see the tutorial for making this sensor board

  5. Sound sensor
    An Electret Condenser microphone (a.k.a Condenser Microphone) is the most common type of transducer that is used to detect or measure sound signals. It functions exactly as opposite of a normal speaker, that is when a sound signal is detected it produces electrical signals. So if you are looking for the transducer to convert sound signals in your environment to electrical signals to detect sound or record voices then this microphone could be the right choice for you. The left circuit has an amplifier and a band pass filter and the right circuit contains a basic amplification stage followed by a comparator(The pot sets threshold voltage).
    Sound sensors

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  1. Relays
    Relays are switches that open and close circuits electromechanically or electronically. Relays control one electrical circuit by opening and closing contacts in another circuit. As relay diagrams show, when a relay contact is normally open (NO), there is an open contact when the relay is not energized. When a relay contact is Normally Closed (NC), there is a closed contact when the relay is not energized. In either case, applying electrical current to the contacts will change their state. Protective relays can prevent equipment damage by detecting electrical abnormalities, including overcurrent, undercurrent, overloads and reverse currents. In addition, relays are also widely used to switch starting coils, heating elements, pilot lights and audible alarms.

    Click on the pic below to see you can build one of such relay boards

    Video and links relating relay boards can be found here
    Controlling Appliances From Smartphone

  2. Motors
    An electric motor is an electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a wire winding to generate force in the form of torque applied on the motor's shaft. Electric motors can be powered by AC or DC sources.

  3. Displays
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    OLED Displays
    An organic light-emitting diode (OLED or Organic LED), also known as an organic EL (organic electroluminescent) diode,is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light in response to an electric current. This organic layer is situated between two electrodes; typically, at least one of these electrodes is transparent. OLEDs are used to create digital displays in devices such as television screens, computer monitors, portable systems such as smartphones, handheld game consoles and PDAs. A major area of research is the development of white OLED devices for use in solid-state lighting applications.

    OLED Displays

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    A TFT display (model name: MCUFRIEND 2.4")

    A thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display (LCD) that TFT technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD.TFT LCDs are used in appliances including TV,monitors,phones,handheld devices,video game systems,PDA, navigation systems, projectors, and car instrument clusters. Useful links below

    1. LCD-Weather-Monitor

    2. Drawing-a-Car-With-Arduino-TFT-Color-Touch-Display


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    P10 LED MATRIX P10 Display Tutorial


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    16*2 Displays

    An LCD is an electronic display module which uses liquid crystal to produce a visible image. The HD44780 based 16×2 LCD display is a very basic module commonly used in DIYs and circuits. The 16×2 translates o a display 16 characters per line in 2 such lines. In this LCD each character is displayed in a 5×7 pixel matrix


    LCD 16*2 DISPLAY

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    MAX7219 Displays

    Click on the image below to open the tutorial


    MAX7219 Display circuit

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  4. Speakers
    A loudspeaker is an electroacoustic transducer; a device which converts an electrical audio signal into a corresponding sound.More can be found in the Amplifier section

    Bluetooth enabled DIY headset

  • GSM modules

    SIM800 is a complete Quad-band GSM/GPRS solution in a SMT type which can be embedded in the customer applications. SIM800 support Quad-band 850/900/1800/1900MHz, it can transmit Voice, SMS and data information with low power consumption. With tiny size of 24*24*3mm, it can fit into slim and compact demands of customer design. Featuring Bluetooth and Embedded AT, it allows total cost savings and fast time-to-market for customer applications. Below are some video and article links.

    SIM900-GSM-Based-Weather-Notifier Project
  • EM18

    EM18 is a RFID reader which is used to read RFID tags of frequency 125 kHz. After reading tags, it transmits unique ID serially to the PC or microcontroller using UART communication or Wiegand format on respective pins. EM18 RFID reader reads the data from RFID tags which contains stored ID which is of 12 bytes. EM18 RFID reader doesn’t require line-of-sight. Also, it has identification range which is short i.e. in few centimetres. RFID reader EM-18 features: 1. Serial RS232/TTL output 2. Operating Frequency is 125KHz. 3. Range is 5-8 cm.
  • 433 MHz Modules

    Want to add wireless capabilities to your next Arduino project, for less than the price of a cup of coffee? Well, then 433MHz RF Transmitter and Receiver Modules are just for you! They can often be obtained online for less than two dollars for a pair, making them one of the most inexpensive data communication options that you can get. And best of all, these modules are super tiny, allowing you to incorporate a wireless interface into almost any project.

  • Bluetooth Module HC05


    Some useful links below
  • Real Time Clock

    RTC means Real Time Clock. RTC modules are simply TIME and DATE remembering systems which have battery setup which in the absence of external power keeps the module running. This keeps the TIME and DATE up to date. So we can have accurate TIME and DATE from RTC module whenever we want.They have backup power as battery. Two most popular devices are DS3231 and DS1307
    DS1307(left) and DS3231

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