I was enlightened about this Battery Less wonder. This is a boon for rural areas and an emergency tool which depend only on your will and your tendons. I found this bright flash of information when i was looking for supercap vendors.
Learn about Supercaps, dynamo and White LED
Richard J. Nelson on the LED Forever Flashlight. – The future of low power lighting is in the use of the Light Emitting Diode, LED. Sooner or later you will buy one or more LED lights or lamps. The two primary advantages of an LED light source is it’s efficient light generation (exceeding that of fluorescent lamps) and long life, typically 100,000 hours. That is 50 to 100 times more life than most of the bulbs in your house.
This is a Linear Dynamo LED Torch which uses a SuperCapacitor to store the energy. Easy to repair and maintain if necessary.
It uses no batteries and requires only the single LED included. You can even leave the flashlight unused in your car’s glove box for years and you’ll always get that all-important light when you need it most. Forever Flashlight lll pays for itself quickly by saving you the cost of batteries and bulbs.
Jonathan Westhues site of Intriguing Projects include A Test Instrument for HF/LF RFID and a compiler that starts with a ladder diagram and generates native PIC16 or AVR code.
Toy SMPS or an Overkill White LED Driver
I sense the load current and control the duty cycle. The PWM pin on the AVR drives the gate of the FET through a couple of BJTs. Note the absence of any input capacitance; Vin looks terrible but it works. The micro power supply section is isolated with an RC.
This is a nice way to start, learn uC and Power electronics in one go. It does not matter if it an expensive solution for LED Lighting. It certainly is an excellent Educational Project.
It may also be useful to use Intelligent Systems (uC and Firmware) to monitor and manage LED Arrays and control their brightness and color. Large Arrays can be Interfaced to PC by XBee for Home/Office or Factory Lighting Automation and Energy Consumption Optimization.
uC Real World Interface
uC I/O is Keyboard and LCD when you Build a calculator or a Text/Morse Communicator. When you control a motor it is Drive/Speed and Direction for Motor and Tacho or Opto Counters for Feedback. In both cases you have Input and Output which is Logic or Analog which has to reach the CPU.