Overview Where I live most of the time, the AC power drops out upon occasion. This used to leave me groping around in the dark for a flashlight. I could have bought a battery-backed up “emergency light” for about US$35, but being basically metal boxes with floodlights attached, they would make my living room look […]
White LED Battery Powered Power Failure Light Read More »
BUT FIRST AN IMPORTANT NOTE: This project uses lethal voltages. If you are not experienced in working with lethal voltages, read this project, but don’t build it. You only have one life, and AC power can take it from you very quickly, or leave you with terrible injuries. When working on high voltages, remember: •
A White LED Night Light Design Read More »
Photo. This is the test circuit -the basic driver is only two transistors, two resistors, the circuit was evaluated using a white LED, but when it was time to button it up and archive it, I replaced the expensive white LED with a cheap green one. Othere LED Driver Circuits on this site: White LED
Series Connected Voltage Boost Circuit for a Battery Operated LED Lantern Read More »
What it is The circuit allows a precision regulated drive current to be set to drive an LED, and in response to a TTL level signal, the LED is switched on and off with rise and fall times of less than 500 nanoseconds and less than 7% overshoot. This was designed for biological experiments to
FAST PRECISION LED DRIVER Read More »
Downloads Download the AVRStudio assembly source for the program: T12astrobe081028A Download the AVRStudio assembly source for the include file: T12astrobe081028A.hex Find updates at www.projects.cappels.org Overview This was designed to flash a pair of LEDs to be mounted on the wing tips of a Parkzone Citabria R/C (remote control) airplane. The unmodified Parkzone Citabria only weights
Remote Controlled (R/C) Airplane LED Flasher using ATTINY12 microcontroller Read More »
Three inductor-free circuits that allow a white LED or UV LED to be driven from one (1.5 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 (1.5 volt) circuit requires six transistors, but it isn’t as
Single and Two Cell White LED Drivers Without Inductors Read More »
Download FreePC project file, gerber and png copper and silk-screen: 1wattledbuck.zip Introduction I have some 1 watt warm white LEDs left over from a project and the application for them was obvious: A better battery operated lamp for use when the power fails, which it does frequently, especially during the rainy season. And this one should
1 Watt White LED Power Supply Circuit for battery operation Read More »
Overview The circuit shown in Figure 1 is capable of driving an LED array requiring up to several amps with a burst of flashes before coming on until power is removed. It is intended to be used as an auxiliary warning light driver. The initial burst of flashes is meant to enhance visual detection of
Attention-Getting Auxiliary Warning Light Flasher/Driver Read More »
Be Careful About Peak Current A note of caution: These LEDs are comparatively expensive, so I suggest putting a small resistor (1 to 10 Ohms) in series with the cathode of the LED and measuring the peak current as inferred from the IR drop using either a scope or a peak detection probe (as described
White LED Drive Circuit using Tiny microcontroller Read More »
An adapter to allow low capacitance probing of high frequency circuits. Overview My boss, Dave, said “Just hold the probe close to the cathode lead.” Dave had worked at Tektronix for many years, and his ability to make difficult measurements was second only to his abilities to manage a company and design clever circuits. Dave’s
Low Capacitance Scope Probe Adapter Read More »
