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Back & Forth Flasher - for16 LEDs (Tony van Roon's electronic design added 4/02) |
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Basic LED flasher circuit using NE555 timer IC - Scroll down to find this one.
This circuit consumes more power, but it's advantage is when you need a variable flash
rate, like for strobe circuits. You can actually use this circuit as a remote control
for strobes that have a remote input. Of course, it has many other applications
besides strobes.....(added 10/05) |
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Basic LM3909 LED Flasher - runs from1.5-Volt battery (Tony van Roon's electronic
design added 3/03) |
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Battery Charge Current Indicator - This circuit turns on a LED whenever it detects
at least 25ma of battery charge current. (added 7/06) ….(designed by David A. Johnson) |
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Battery Equal Charge Indicator - The circuit below illuminates an LED to indicate
unequal charges between two 12 volt lead batteries. It can be used to verify that two
batteries are connected in parallel or isolated since the LED will be off when the
voltages are equal within a tollerance, or on if the voltage difference is greater
than 100 millivolts. Three comparators....(added 5/09) |
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Bi-Color LED Indicates Power/Fault - EDN 12/05/96 Single LED indicates both power
on and blown-fuse conditions. (added 9/04) |
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Bicycle Back Safety Light - this circuit has been designed to provide a clearly
visible light, formed by 13 high efficiency flashing LEDs arranged in a
pseudo-rotating order. Due to low voltage, low drain battery operation and small size,
the device is suitable for mounting on bicycles as a back light, or to put on by
jogger/walkers (schematic added 06/07/08) |
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Big 7-Segment LED Display Board with SPI Interface - The circuit uses a
serial-in-parallel out shift register, 74HC595 for receiving serial data from
uController board. See example of U5 in schematic, SER is for data input, SRCLK
is shift clock and RCLK is Latch clock. Each data bit is shifted into register
on rising edge of shift clock. When all data bits are shifted into 8-bit
register, rising edge of RCLK will clock data to be latched at each output
bit, i.e. QA QH.... (added 6/06) |
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Big LED Clock - (circuit / schematic added 5/03) |
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Binary Coded Decimal Bcd Clock - The clock circuit above uses seven ICs and 19
LEDs to indicate binary coded decimal time. The LEDs can be arranged (as shown in
example above) so that each horizontal group of 3 or 4 LEDs represents a decimal digit
between 0 and 9 and each individual LED represents a single bit or (binary digit) of
the value. Binary digits....(electronic schematic / circuit added 04/03/02) |
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Birthday Heart - This circuit was made for my wife's birthday. It is capable of
flashing five strings of LED's with different frequencies. It also has a connector for
an 8 Ohm loudspeaker and two connectors for the small PCB's that are contained in
musical greeting cards. In this way the circuit will play alternatingly two room
filling tunes at regular time intervals. After a w....(electronic design added 6/07) |
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Buck Configuration High-Power LED Driver - Microchip Application Note Published
4-Jan-06 (app note added 2/06) |
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Buck IC Boosts Battery Voltage for White LED - 04/24/03 EDN-Design Ideas:
White-light LEDs are finding ir way into many markets that incandescent bulbs once
served. Flashlights are among newer applications in which reliability,
ruggedness, and ability to control power draw of LEDs make se devices
attractive. With incandescent bulbs, power management for device is a
simple on-off switch.....(design idea added 1/05) |
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Buck regulator controls white LED with optical feedback - (Video Design Ideas- EDN,
10/25/07) -- By using optical feedback, you can stabilize the output level of a
high-intensity LED. (electronic design idea added 9/08) |
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Buck/Boost Charge Pump Regulator Powers White LEDs from a Wide 1.6 Volt to 5.5 Volt
Input - Maxim Application Note #1021 (app note added 5/08) |
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Buck/Boost Reference Design - This reference design presents an alternative to
typical boost power regulator. A buck converter IC is used to generate a higher
voltage needed by white light LED power from a Ni-Cd battery. This circuit
operates by turning high switch on, connecting battery voltage across
inductor. Once sufficient energy is stored in inductor, ... (added
6/06) |
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Buck/Boost-Based LED Drivers using the HV9910 - Supertex Semiconductors (app
note added 2/06) |
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Buck-Based LED Drivers using the HV9910 - Supertex Semiconductors (app note
added 2/06) |
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Buffer Amplifier & LED Improve PWM Power Controller's Low Load Operation -
09/15/05 EDN-Design Ideas: PWM IC is enhanced with discrete components for wider-range
operation.....(design idea added 3/06) |
