LED lights manufacturer introducing common three kinds of LED bulbs light power
there is the most commonly used LED dimming power supply: LED SCR dimmer power, LED0/1 - 10 v adjustable light power supply, PWM dimming power supply. Other operation principle is that move light through manipulation of the current and voltage, the frequency range of the output to the LED dimming function, then follow a small make up together to understand.
1, LED SCR dimmer power
silicon controlled dimmer earlier before they are applied to the incandescent lamp and energy-saving lamp dimming method, and is applied to the LED dimming the broader range of a dimming method.
it is the operation principle of the input voltage waveform after conduction Angle cutting wave, a tangential output voltage waveform. Applied the principle of tangential cutting back output voltage effective value, in order to reduce the normal load ( Resistance load) The power. Silicon controlled dimmer the advantage of high work efficiency, function.
2, 0/1——领导 10 v dimmer power
power supply design with a control chip, 0 When 10 v dimmer, through 0 10 v voltage changes, changes in the power supply output current, light reduction. For example: when 0 10 v dimmer modulation to 0 v, the current drop to zero, the light brightness is also closed status ( There is a switch) When 0 10 v dimmer augmenting the largest 10 v, output current will reach 100% of the output power, brightness will be 100%. ( The output voltage is the same) 。
1 - 10 v dimmer principle: as mentioned to clarify, just dimmers is 1 10 v: when resistance dimmers adjust to minimum 1 v, the changes of the output current is 10%, such as to 10 v ( Transferred to the largest) , the output current will reach 100% of the output power, brightness will be 100%. ( The output voltage is the same) 。 Note: 1 There is no switch function, 10 v lamps can not be transferred to the minimum closed role!
3, PWM dimming power supply
digital dimming is also called the PWM dimming, open and closed after the PWM wave LED to change forward current conduction time, to reach the brightness control function. The method on the basis of the characteristics of human eye on brightness shine sensitive enough, when the load when the LED light is dark. If the brightness of more than 100 hz frequency, the human eye to see is uniform brightness, rather than the LED on. PWM after eyelid bright and dark moment share realize brightness, in a PWM cycle, because the human eye is more than 100 hz in the shining light, the brightness of the perception is a cumulative process, namely bright moment in the whole cycle of the higher the share, the brighter the human feeling. But about some high-frequency sampling equipment, such as high frequency sampling camera, sampling may just to gather the LED to the dark of the image.