Electronic projects


you are here: home page :: projects :: Light & LED :: LED applications :: LEDs or Lamps Sequencer

LEDs or Lamps Sequencer

Very simple, versatile modular design
No limits to the number of modules used in the ring

Circuit diagram using LEDs:

Circuit diagram using Lamps:

Parts:
R1 1K5 1/4W Resistor
R2 680R 1/4W Resistor (Optional, see text)
C1 47F 25V Electrolytic Capacitor
D1 LED any type
Q1 BC337 45V 800mA NPN Transistor
P1 SPST Pushbutton
LP1 Filament Lamp 12 or 24V (See text)

Comments:
The purpose of this circuit was to create a ring in which LEDs or Lamps illuminate sequentially. Its main feature is a high versatility: you can build a loop containing any number of LEDs or Lamps, as each illuminating device has its own small circuit.
The diagrams show three-stage circuits for simplicity: you can add an unlimited number of stages (shown in dashed boxes), provided the last stage output was returned to the first stage input, as shown.
P1 pushbutton purpose is to allow a sure start of the sequence at power-on but, when a high number of stages is used, it also allows illumination of more than one LED or Lamp at a time, e.g. one device illuminated and three out and so on.
After power-on, P1 should be held closed until only the LED or Lamp related to the module to which the pushbutton is connected remains steady illuminated. When P1 is released the sequencer starts: if P1 is pushed briefly after the sequence is started, several types of sequence can be obtained, depending from the total number of stages.

Notes:
If one LED per module is used, voltage supply can range from 6 to 15V.
You can use several LEDs per module. They must be wired in series and supply voltage must be related to their number.
Using 24V supply (the maximum permitted voltage), about 10 LEDs wired in series can be connected to each module, about 7 at 15V and no more than 5 at 12V.
The right number of LEDs can vary, as it is depending by their color and brightness required.
Using lamps, voltage supply can range from 9 to 24V. Obviously, lamp voltage must be the same of supply voltage.
In any case, lamps may also be wired in series, e.g. four 6V lamps wired in series can be connected to each module and powered by 24V supply.
If you intend to use lamps drawing more than 400mA current, BC337 transistors should be substituted by Darlington types like BD677, BD679, BD681, 2N6037, 2N6038, 2N6039 etc.
As Darlington transistor usually have a built-in Base-Emitter resistor, R1 may be omitted, further reducing parts counting.
Sequencer speed can be varied changing C1 value.
A similar design appeared in print about forty years ago. It used germanium transistors and low voltage lamps. I think the use of LEDs, silicon transistors, Darlington transistors and 24V supply an interesting improvement.

author: RED Free Circuit Designs
e-mail:
web site: http://www.redcircuits.com/
project categories:
folder Audio (49)
folder Power & high voltage (43)
folder Radio (23)
folder Light & LED (31)
folder Tools & measurement (40)
folder Telephone (18)
folder Automotive (10)
folder Microcontrollers (12)
folder Sensors & control (47)
folder Timers & oscillators (40)
folder Miscellaneous (26)

StumbleUpon button

Share this page
Bookmark and Share
project subcategories:
All subcategories
music & light
LED applications
other

similar projects:
6V Ultra-Bright LED Chaser
Bicycle back Safety Light
Dancing LEDs
Dark-activated LED or Lamp Flasher
Fading LEDs
Knightrider lights for model cars
LED Chaser
LED or Lamp Flasher
LED or Lamp Pulser
LED Torch

recently added projects:
Doorbell for the Deaf
High Quality Intercom
Combinational Conjuring Trick
POT-PLANT POWER
Ultrasonic Dog Whistle
Quiz Circuit
LED Torch
Insect Repellant
Speaker Microphone Circuit
Magic Wand Conjuring Trick.

most popular projects:
Led display digital Voltmeter
500W low cost 12V to 220V inverter
Low pass filter - Subwoofer
Metal Detector
High And Low Voltage Cut Off With Time Delay
Basic UPS Power Supply
2N3055 Power Amplifier
200W audio amplifier
LED Torch
100W RMS Amplifier


DIY Electronics Projects

Promote Your Page Too