Modified 2 stage blinker circuit for LEDes and brakelight

This circuit is like an advanced version of first blinker circuit, it uses 2 astable circuits, not 2 IC. We can use 556 here. 2 Astable multivariator of Low and High frequencies are cascaded and gives good programmed pulse like 1 long pulse and 2 to 5 sort pulse (Depends upon setting).

The below circuit shows Multi-function blinker circuit

Components:

IC: U1A,U1B : LM556 (Duel timer IC)
Resistors: R1: 1.2K, R2:1K*, R3 750 Ohm, R5:220 Ohm
Pot: R4:1K Ohm, (R2:2K*)
Diode: D1,D2,D3: 1N4007.
Transistor: Q1: MJE200 or any power NPN transistor.
Capacitors: C1:100uF, C2,C4:10nF, C3:22uF.

Description:

• The First stage multivibrator is set to 5 hz, 50% duty cycle (on off 5 times in second ;) ).
• The second stage is a variable one. it varies from 15hz to 160hz
• When first stage in OFF state the second stage is ON -> High only
• When first stage is ON, The trigger circuit will activate second stage and low frequency pulses

Output graph:

PCB Layout & Project files:

• Multisim
• Cadsoft Eagle

If any problems, Comment below

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Simple 12V blinker (strobe) For Horns,Brakelight etc

Its a simple 555 Astable multi-vibrator circuit, for blinking 12V DC.

• It can be connected for brake light, blinking brake-lights draws more attentions than normal ones.
• Can be connected for horns for stroked sound (relay is needed).
• Can be used with LED strips.

Below schematic shows circuit of blinker.

Components:

1. U1: LM555
2. Resistors: R1:100 Ohm, R3:220 Ohm
3. Variable resistor (Potentiometer)R2 2K ohm
4. Capacitors: C1: 22uF(electrolytic),C2: 10nF (Ceramic or tantalum).
5. Transistor Q1 MJE200G or any NPN power Transistor
6. Diodes: D1: 1N4007, D2: 1N4745 (16V zener) -1 
7. Relay*.

* Ground may be body or battery -ve terminal.
*No need of 10K resister at output.

Connection for brake light:

PCB layout & Project files:

 

Project:

• Multisim Project: Downlaod

• Eagle cad PCB project : Download

If You have any problems, Comment below.

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