How to quickly judge LED bulb strobe

Many people now use LED bulbs at home

After all, LED bulbs are also cheaper

and it is the most energy efficient in terms of power consumption

Please disassemble this LED bulb below. 

Look at what the internal circuit is like

This is a 2W removed Light bulb.

If it is difficult to open the lampshade directly

use a hair dryer to blow The glue on the side

The sealant is softened by heat

It is easy to open

Open to see

There is a LED control circuit and a LED aluminum substrate

The LED aluminum substrate has many LEDs

LEDs are divided into two groups

6 LEDs in each group are connected in series

LED lamp control circuit components

Includes resistors, capacitors, diodes

You can see that the board is very simple

There are not many components included

The circuit diagram of the above board is like this

only some of the LEDs are drawn in the picture

capacitor C1 and resistor R1 Resistor-capacitor step-down circuit

Rectified by bridge rectifier circuit after step-down

Rectification Filter with capacitors

Then, the output voltage of the current limiting resistor R3 lights up 2 sets of LED lights

Only need these components to make a LED bulb

Do you feel very simple?

But an LED bulb like this is actually a strobe.

Circuit Simulation Waveform of Voltage

The lower the strobe, the less damage to the eyes

The quality LED bulb uses a constant current chip to drive the LED

This strobe will be lower

China industry standard strobe requirement for qualified products is 3125 Hz

How to quickly distinguish the strobe of LED?

The method is very simple

is the camera directly on the phone

Focus on the illuminated LED lights with a camera

You can separate the strobe levels

The strobe light bulb is not much different under the lens and the naked eye.

Low-flash LED bulb

Strobe light bulbs, frequently fluctuating lines on the phone screen

even flashing

Strobe LED bulbs

Equipped with a constant current chip, which can effectively reduce stroboscopic light

General bulbs with constant current chips will be more expensive

Try to test your car's bulbs are not too big!