This circuit basically works on the charging and discharging of capacitors.
Npn transistor flasher circuit.
Police style strobe light circuit is operating using 555 ics and these ics can operate a limited amp and current.
However on proteus isis it doesn t i have to change the 330k to 1500k for it to work on proteus.
But now we use 2 npn transistor.
The above circuit uses a combination of bc 557 and bc 547 transistors in such a way that bc 547 npn transistor conducts for a very brief time making the led light.
After making a circuit connect 9v battery to the circuits.
R1 2k7 r2 100 ohms t1 bc 547 c1 100 uf to 470 uf.
I like blinking 2 led circuit using npn transistors.
This interval can be varied by varying the value of the capacitor.
We normally see it in a lot of circuit as.
2 piece of timer ic555.
Active 3 years 11 months ago.
This led flasher circuit is very easy and simple and there is no ic used.
Use 9v or 12v battery or adaptor for this circuit.
2 piece of 1m 1000k resistor.
Ask question asked 3 years 11 months ago.
The resistor r and capacitor c determines the timing of the flasher and the period is proportional to r c.
Circuit diagram blinking led circuit.
The combination of resistors and capacitors determines the timing of the flasher and the time duration is proportional to r x c.
But the supply voltage not be less than 9v otherwise the circuit might fail to work correctly.
This circuit can be operated using dc 6 12v supply.
Components for the circuit.
Led flashing start by a specific interval.
We call it astable multivibrator.
Often we know it 2 led flasher circuit in this we use pnp transistor.
This circuit uses a bc557 pnp transistor connected to a bc547 npn transistor in such a way so that the bc547 conducts for a very brief time making the led light.
The flashing rate could be varied either by changing the value of r1 or c1 or both together.
Parts list for the proposed single transistor led flasher circuit.
There are many circuits here is one of the blinking circuits.
Increasing the value of the capacitor will result in increasing the interval time of the led.
So to add more than 8 leds you should use transistor to control the power other wise your ics may damaged.
How to make simple led flasher using transistor follow us on.
Both npn transistor you can use of bc547 548 or 2n2222.
This circuit contains both npn and pnp transistors.
Blinking 2 led circuit using npn transistors.