High power LED flashlight circuit, 6 LED for 1.5V AA battery

This high power LED flashlight circuit look like a torch by use on 1.5V battery only so it can be used. Since small so Easy to carry in various places. And also very bright as well.

The technical information

Power supply : one 1.5V AA battery.
Maximum current used 200mA
Uses 6 white LED.
Small size PCB.

How it works

As usual, the LED light when a voltage is 1.8V or 2V,
We need a way to increase the voltage to rise, by the switching supply mode in step-up DC to DC converter circuit.

High power LED flashlight circuit, 6 LED for 1.5V AA battery

Figure 1 Circuit diagram of High power 6 LED Flashlight for 1.5V AA battery.

As Figure 1 is Circuit diagram of this project. By operation of the circuit is determined by Coil and C2. Which will serve as the production cycle frequency. The LC Frequency circuit with capacitors and capacitor alternately, cause frequency.

When we apply power supply voltage to circuit, the transistor TR1 will working. Then TR2 will work as well. In the meantime, C2 will charge store current. So all LEDs will go out. But when fully charging, TR1 will stop working result C2 discharge to all LEDs glow.

Since the charging and discharging very fast, cause we see them same still brightness. The capacitor-C1 will be filter the current to smooth.

How to builds.

This project is small and a few part so we can use a perforated board. Or use real PCB as Figure 2. Then assemple all parts on PCB and wiring as Figure 3.
Real PCB of high power 6 led flashlight for aa battery
Figure 2 the real PCB of this project.

Components layout and circuit assembling
Figure 3 the components layout.

The L1-inductor is 100uH as Figure 4 I measure it show you. And you can use any type that look like it.
Coil is about 100uH

Figure 4 Coil is about 100uH.

High power 6 LED Flashlight for 1.5V AA battery
Figure 5 The High power 6 LED Flashlight projects for 1.5V AA battery.

When completed circuit assembly Supply voltage range of 1.5V to the circuit.
Then slide the switch to position ON. The All LEDs will lit, the circuit is ready for use.
As Video below.

I want to see wavefrom across LEDs (all in parallel) through an oscilloscope panel.
We will see that high amplitupe about 3Vp-p it cause LEDs glow.

Note: AA battery we should is kind of alkali house. Because high performance

The parts list.
Resistors 0.25watts
R1: 10K
R2: 6.8K
R3: 100 ohms

Electrolytic capacitors
C1: 220uF 16V

Ceramic Capacitors
C2: 680pF 50V

Inductors coil
L1: 100uH Please how to build it here
TR1: CS9012__ 0.8A 40V PNP Transistors.
TR2-TR4: CS9013__0.8A 40V NPN Transistors.

PCB, 1.5V AABattery, etc.

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I always try to make Electronics Learning Easy.

Apichet Garaipoom

I love the electronic circuits. I will collect a lot of circuit electronics to teach my son and are useful for everyone.
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