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.
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.
Figure 4 Coil is about 100uH.
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.
R3: 100 ohms
C1: 220uF 16V
C2: 680pF 50V
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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