Led's drive is generally referred to as the Led's Luminous Module Controller, which controls the current. If the control current is not good, the lamp may be damaged. Sometimes the current and voltage can be very unstable, then the driver will play a role. So LED drives are very good to check for damage during use. If it is damaged, it can cause the light to dim or turn off directly, and it can also cause flashes. Led driver is an electronic device that drives the LED light to emit light and work normally. It is equivalent to the heart of the LED lamp. When the driver is in problem, the whole LED lamp will be in problem. Drivers can be categorized (1) Constant current: A. The output current of the constant current drive circuit is constant, but the output DC voltage varies in a certain range with the magnitude of the load resistance value. Load resistance value is small, output voltage is low, and the larger the load resistance value, the higher the output voltage is. B. Constant current circuits are not afraid of short-circuit loading, but full open loading is strictly prohibited. C. Constant current drive circuit for LED is ideal, but relatively expensive. D. Pay attention to the maximum withstanding current and voltage value used, which limits the number of LEDs used. (2) Voltage regulator: A. When the various parameters of the voltage regulator circuit are determined, the output voltage is fixed, but the output current changes with the increase and decrease of the load. B. The voltage regulator circuit is not afraid of load opening, but it is strictly forbidden to completely short-circuit the load. C. Drive the LED with a regulator-driven circuit, each string needs to be added with a suitable resistor to make each LED display brightness average; D. The brightness will be affected by the voltage change coming from the rectifier.

 Voltage regulator (AVR) is specially designed for AC brushless generator with matching base wave, harmonic compound excitation or permanent magnet generator excitation (PGM system). The voltage regulator realizes the automatic adjustment of the output voltage of the generator by controlling the excitation current of the alternating current exciter of the generator. Generator voltage regulator can be used for normal 60/50Hz and mid-frequency 400Hz single-machine or parallel-running generators. It is important to minimize the output ripple and transient of the switch regulator, especially when supplying power to noise-sensitive devices such as high-resolution ADC, the output ripple will appear distinctly spurious in the ADC output spectrum. To avoid reducing signal-to-noise ratio (SNR) and stray-free dynamic range (SFDR) performance, switch regulators are usually replaced by low-pressure differential regulators (LDOs), sacrificing the high efficiency of switch regulators in exchange for cleaner LDO output. Understanding these artifacts will enable designers to successfully integrate switch regulators into more high-performance, noise-sensitive applications. Output ripple and switch transient depend on the regulator topology and the value and characteristics of external components. Output ripple is the residual AC output voltage, which is closely related to the switch operation of the regulator. Its base frequency is the same as the switch frequency of the regulator. Switch transient is a high frequency oscillation that occurs during switch switching. Their magnitude is expressed in terms of the maximum peak voltage, which is difficult to measure precisely because it is highly correlated with the test settings. The inductance and output capacitance of the regulator are the main components that affect the output ripple. Smaller inductance produces faster transient response at the expense of larger current ripple; A larger inductance makes the current ripple smaller at the expense of a slower transient response. The output ripple can be minimized by using a low effective series resistance (ESR) capacitor.