LED lamp brightness change control method suitable for singlechip processing and device thereof

Abstract

The invention discloses an LED (Light Emitting Diode) lamp brightness change control method suitable for singlechip processing, which comprises the following steps: judging whether an expected duty cycle discrete value EP is equal to a current duty cycle discrete value CP or not, if not equal, calculating the duty cycle change prediction interval time ITC, wherein ITC is equal to FP / CP, and the FP is a discretization value of the 100 percent duty cycle; comparing the ITC with a preset allowable interval time ITM, if the ITC is larger than the ITM, allowing the change interval time IT of the duty cycle with the duty cycle discretization value plus or minus 1 to be equal to ITM; if the ITC is less than or equal to ITM, allowing the IT to be equal to ITC; judging whether the IT is reached or not, if yes, comparing the EP and the CP; if the EP is larger than the CP, adding 1 to the CP; if the EP is less than the CP, subtracting 1from the CP; and repeating steps 1-9 till the CP is equal to the EP. The invention also discloses a device for the realization of the method. According to the invention, less singlechip resource is consumed, and smoother brightness change is obtained.

Description

technical field [0001] The invention relates to a method and a device for controlling the brightness change of an LED lamp suitable for processing by a single-chip microcomputer. Background technique [0002] People's subjective brightness perception has a logarithmic relationship with physical brightness. In order to obtain a more comfortable brightness change, the brightness of LED lights is generally controlled to change exponentially with time. The brightness adjustment of LED lights is generally realized by adjusting the duty ratio of the signal. When the duty ratio changes exponentially with time, people feel more comfortable about the change of LED brightness. [0003] In order to realize the control of the exponential curve, the following methods are generally used at present: 1. Directly carry out Taylor series expansion on the exponential curve; [0004] The first method to perform Taylor series expansion can control the smooth brightness feeling, but it requires ...

AI Technical Summary

Problems solved by technology

[0004] The first method to perform Taylor series expansion can control the smooth brightness feeling, but it requires a lot of calculations, which consumes a lot of time of the CPU in the microcontroller and takes up more program storage space; the second method uses polylines For fitting, the CPU calculation time is less, but if there are few segments, you cannot get a smooth brightness feeling, and if there are many segments, it will take up more program storage space; the third method can control the smooth brightness by looking up the table Feeling, and the CPU calculation time is the least, but if the resolution of brightness control is higher, it will take up more program storage space, for example, 0.1% resolution will use 2000 bytes

Images