Tag Archives: Led

8 Digit Numerical 7 Segment SPI Display Shield for Arduino UNO

8 Digit serial numerical display shield for Arduino has been designed for various applications like digital clock, stop watch, score display, temperature meter, frequency counter, digital meters etc. The circuit uses popular MAX7219 IC and two common cathode 0.5inch red seven segment displays. The MAX7219 is a compact, serial input/output common-cathode display drivers that interface Arduino UNO to 7-segment numeric LED displays of up to 8 digits. Included on-chip are a BCD code-B decoder, multiplex scan circuitry, segment and digit drivers, and an 8×8 static RAM that stores each digit. Only one external resistor R1 provided to set the segment current for all LEDs. A convenient 3-wire serial interface connects to all Arduino UNO. Individual digits may be addressed and updated without rewriting the entire display. The MAX7219 also allows the user to select code-B decoding or no-decode for each digit. The devices include a 150µA low-power shutdown mode, analog and digital brightness control, a scan-limit register that allows the user to display from 1 to 8 digits, and a test mode that forces all LEDs on. The project works with 5V DC and SPI interface connected to Arduino Digital pins D4, D5 and D6.

8 Digit Numerical 7 Segment SPI Display Shield for Arduino UNO – [Link]

10 LED Bar-Graph Display with Op-Amp Shield for Arduino Nano

Arduino Nano Bar-Graph display with universal op-amp shield consists of 10 LEDs and single low voltage general purpose LMV321 op amp including few capacitors and resistors connected to op-amp pins. The op-amp proto area can be configured without any modifications to the board and all that is necessary is to select the correct resistors and capacitors. The other optional components can be left open or shorted depending on the configuration desired. All 10 LED comes with current limiting series resistors connected to digital pins D2 to D11 of Arduino Nano, Nano analog pin A0 used as input, the input can be used directly as voltage input to measure the voltage and display on Bar-graph.

0 To 5V Bar-graph volt meter with 0.5V step is simplest project possible with the shield, many other sensor based application possible using op-amp as signal conditioning amplifier.

Code for Simple Bar-Graph Voltmeter with 0-5V range is available here.

https://www.arduino.cc/en/Tutorial/BarGraph

10 LED Bar-Graph Display with Op-Amp Shield for Arduino Nano – [Link]

1Amp Constant Current LED Driver Shield for Arduino Nano

1A Constant current LED driver shield for Arduino Nano has been designed for verity of LED related applications. The shield provides accurate LED current sink to regulate LED current in a string of LEDs or single LED. The LED current is mirrored from the current flowing from the RSET Preset PR1. On board 1W LED is used for testing purpose. External high Wattage LED or multiple LED string can be connected by pulling two wires from the PCB and this shield fit directly on back side of Arduino Nano. Shield also has on board tactile switch connected to Digital D2 pin using pull down resistor if required for any application. On board preset helps to set the maximum constant current. PWM input pin connected to Digital pin D6 of Nano to control the LED intensity. Example code FADE-IN/FADEOUT helps to test the shield.

1Amp Constant Current LED Driver Shield for Arduino Nano – [Link]

Chromatron – Wifi Pixel Controller

Chromatron is an open source Wifi pixel controller designed to make LED pixel projects easy and fun.

Hi, I’m Jeremy! I’ve designed a toolkit for making art with LED pixel strips, and I’d like to share it with you! Chromatron takes custom designed hardware and feature-packed firmware, sprinkles it with some Python, and serves up a delicious new platform to help you transform your world into a psychedelic dreamscape.

HOW-TO: Music Reactive Desk Light

@ natural-nerd.com build a sound reacting LED light using Arduino:

Hi! In this build we’ll make a good looking light that dances to all sounds and music, using simple components and some basic Arduino programming. It makes an awesome effect while standing on the desk when gaming, playing music, and anything else that makes sound really. Let’s get going!

HOW-TO: Music Reactive Desk Light – [Link]

RASPILIGHT: an open project for Ambilight TV effect

LucaBellan @ open-electronics.org  re-created the Ambilight TV effect on any other TV using Raspberry and Kodi. He writes:

The screen’s edges are divided into logic sectors, and each sector is associated with a specific LED and, by making a color average of the pixels, you can find the color to set to be reproduced by the LEDs; this operation is repeated for all the LEDs mounted on the TV and all of this is repeated hundreds of time per second in order to provide synchronicity and maximum smoothness to the colors projected around the TV.

With RaspiLight we can re-create this technology and apply it to any flat-screen TV, but there’s more: even when the TV is off, we can control the system through an Android or iOS app and create static or dynamic light effects and make the TV an animated lighting point and not just a simple lighting piece of furniture.

RASPILIGHT: an open project for Ambilight TV effect – [Link]

The Aurora Boxealis – A Color Sensing and Mirroring Project

Besides looking damned good on an otherwise bland and ordinary desk, this project is about more than just being attention grabbing eye candy.  It’s about demonstrating a small portion of our single board computer capabilities by hooking up a color sensor, RGB light strip, and enclosing it in a nice looking wooden enclosure.  We’re dubbing it the “aurora boxealis”, and it’s made to stand out from the crowd at trade shows and provide a fun, interactive way to professionally demonstrate an interesting sensor, in this case a color sensor.  Grabbing a color swatch from the table and placing it on the top of the box will trigger the lights to mirror that color.

The Aurora Boxealis – A Color Sensing and Mirroring Project – [Link]

Temperature Controlled Fan With LED Status

This is a simple fan controller with single LED temperature status light using an ATtiny85 microcontroller and DS18B20 temperature sensor. The fan is turned on/off based on temperature sensed and the controller goes in sleep mode when the temperature drop below a predefined threshold.

Simple ATtiny85 fan controller to turn a fan on/off based on temperature. Includes an LED as a temperature indicator. LED is dim at start of fan on temperature and blinks when above a max temperature. Fan is not PWM controlled since I am using a small 5V fan which is quiet running at 100%. The controller is in sleep state while the temperature is below the minimum threshold and wakes up every ~8 seconds to recheck the temperature. When temperature is above minimum threshold, the controller will stay awake checking every second till the temperature falls below the minimum threshold. The code uses ds18b20 library by Davide Gironi.

Temperature Controlled Fan With LED Status – [Link]

Sound Activated LED Light With Timer

Clap to light switch with timer project is very useful project for power saving applications. The project switches on the LED light for 45 to 60 seconds when receives two clap sound. This project can be used in store room, toilets, dark area where switch is not visible, night lamp, places where light on off switch is not accessible easily.

Single transistor used as microphone preamplifier, diode converts AC signal in to DC , and PIC micro-controller take care of LED On/OFF Time, LED  time depends on two jumpers J1, J2 which provides four options s 45, 50, 55, 60 seconds. MJE3055 transistor used in output to drive LED, one series resistor R10 helps to control the current going through LED, R10 can be alter as per LED Voltage and current. 3V to 12V LED with maximum current 500mA can be used. Use higher current Darlington transistor like TIP147 for higher current Load. Onboard potentiometer trimmer for sound sensitivity adjust. D1 power LED.

Sound Activated LED Light With Timer – [Link]

PICTIL – Remake of the TIL311 hex LED display

Yann Guidon @ hackaday.io rebuild the TIL311 hexadecimal display using a pic microcontroller. He writes:

The TIL311 is a nice but expensive, obsolete, power-hungry hexadecimal display. It would be cool to make a tiny module with similar functionality which solves its shortcomings. A 20-pins PIC is a solution but other decoding chips could work too. The PIC16F527 is one of the cheapest 20-pins PICs (sub-dollar), but it can’t implement the latch pin as fast as the original TIL311.

PICTIL – Remake of the TIL311 hex LED display – [Link]