A smart bulb is an internet or Bluetooth-capable LED light bulb that allows lighting to be customized, scheduled and controlled remotely. Smart bulbs are among the most immediately successful offerings in the growing category of home automation and Internet of Things (IoT) products. In today’s market many types of smart bulbs are available form price $10 to $100. But, can you think you can convert a low price led bulb to a smart bulb easily? Today I will show you how I converted a cheap Chinese led lamp to a Smart Lamp.
Before going to the details let me explain the basic features of my Smart Lamp.
1. The lamp can be controlled from Android phone using Bluetooth.
2. It can be used as true white lamp as well as color lamp and can produce 16 million colors.
3. Brightness and color can be controlled from smart phone.
4. It operates directly from AC mains.
Step 1: Collect the Materials
1. Low Price LED Light Bulb (ebay.com)
Many types of LED light bulbs are available in local market. Different types of wattage rating are also available. Select one as your requirement. I bought a $1.5, 7W LED Bulb from my local market.
2. Arduino UNO R3 (ebay.com) (gearbest.com)
As we want to include some control mechanism and communication features to our light bulb a microcontroller will be required. I selected Arduino UNO because developing prototype using Arduino is very easy. I just programmed the board, tested it and then removed the microcontroller from the UNO board. Then, I put the microcontroller to the circuit board.
3. HC-05 Bluetooth Module (ebay.com) (gearbest.com)
For communication with the light bulb from my smart phone I want to use Bluetooth and for the reason I selected low price HC-05 module. The module is working as slave mode and my phone as master.
4. RGB-LED 4 pin 5mm (8pcs) (ebay.com)
There is some power limitation as well as space limitation and for that I used only 8 RGB LEDs. RGB leds are very cool. These have four pin. One is the common and other three pin for three basic colors. You may use datasheet for details pin configuration. Using PWM 16million color can be generated from an RGB led.
5. Op to coupler TLP627 (ebay.com)
Op to coupler has an important role in our project. In the lad light bulb all LEDs are connected in series and connected to 100 V DC. Very simple transformer less power supply is used for step down and rectification and I found enough ripple in the output. If we want to on/off and control brightness of the lamp remotely we have to use a switch between rectifier output and LEDs. A high voltage transistor can be used for the job but for driving the transistor we have to connect it to the microcontroller. As transistor are working in high voltage it may damaged the microcontroller if you directly connect the base of the transistor to the microcontroller. So, an isolation is required between transistor and microcontroller and for the reason I selected op to-transistor instead of general transistor. It is a high voltage op to-transistor and can handle 150mA current which is enough for our circuit.
Read More: Convert $2 LED Lamp to $50 Smart Lamp