Simple LED driver circuit

Friends, you may have seen many circuits on the Internet showing how we can make a simple driver for LED.
Actually, the driver of the LED is the circuit which gives LED the constant current.
And as you know that the LED market is growing fast day by day so we need a cheaper solution.
Today we will tell you about such a driver which is available on the internet.
We will analyze it and eventually give feedback.
The circuit given below is a simple LED driver with two transistors and two resistors.
The purpose of this circuit is to generate constant current for the LED from a 12V battery.
The battery voltage will be from 10.5V to max 14.2V.

We created this circuit in our laboratory and tested it on the value of various resistors.
Some results of the test are given below.
The value of voltage is in volts and the value of current is in mili ampere.

S.No.	Voltage	R6=4.7 R R5=2.2 K	R6=4.7 R R5=2 K	R6=4.7 R R5=1.5 K	R6=4.7 R R5=1 K
1	14.2	143	144	148	152
2	13.5	142	143	147	152
3	12.8	141	142	147	151
4	12.2	139	141	146	150
5	11.5	131	132	134	134
6	10.8	71	71	71	71

You can see both its results and graphs.
It looks like working perfectly for the range it is designed.
So its conclusion is that if we start this circuit in the market in a cheap price, then it will definitly work.

Author
Aniruddh Kumar Sharma
--Ani-Lab--