3v white led driver circuit

Three inductor-free circuits that allow a white LED or UV LED to be driven from one ( volt) or two flashlight cells (3 volts total) are described. The circuits on this page are: The two cell (3 volt) circuit four transistors. The simple single cell ( volt) circuit requires .  · Jim Keith This V LED driver is more of a fun learning experiment than a practical circuit. While the TLC can indeed drive a 3V white LED using the inductive discharge technique, it typifies the kind of problems present in low voltage circuits. Two circuits are presented: Basic LED Driver and Bootstrapped LED Driver.  · Led Driver/Controller for v 5v circuit i got it working an before i hooked it up to my microcontrollers i tested it with some 3v batteries(CR) leaving out the R1 resistor. it worked. then i put 3 1k resistors there. And used it with an www.doorway.rus:

Pros: consistent LED performance with any power supply and LED's - costs about $1 - only 4 simple parts to connect - efficiency can be over 90% (with proper LED and power supply selection) - can handle LOTS of power, 20 Amps or more no problem. - low "dropout" - the input voltage can be as little as volts higher than the output voltage. - super-wide operation range: between 3V and 60V input Cons: must change a resistor to change LED brightness - if poorly configured it may waste as. Led Driver/Controller for v 5v circuit i got it working an before i hooked it up to my microcontrollers i tested it with some 3v batteries(CR) leaving out the R1 resistor. it worked. then i put 3 1k resistors there. And used it with an arduino. Three inductor-free circuits that allow a white LED or UV LED to be driven from one ( volt) or two flashlight cells (3 volts total) are described. The circuits on this page are: The two cell (3 volt) circuit four transistors. The simple single cell ( volt) circuit requires six transistors, but it isn't as bright as the two cell circuit.

The low V feedback voltage offers higher efficiency in white LED driver applications. The MP regulates the output voltage up to 36V with e. 7 Ara The resistor is just a safety feature to save the battery (and LED) from a short circuit current overload. As a final thought, a CR will not. regulates LED current even when the input voltage is VIN = 3V. µs/DIV. G 4 WHITE LEDs. ILED = 15mA. CIRCUIT ON FIRST PAGE. OF THIS DATA SHEET.