Note: The color or brand of the components may be different in different periods, but the grade is guaranteed to be the same.This price is a price, the finished board, the actual product is shown in the pictureWith delay and DC protection function (default 1.8V start control, DC sensitivity can be adjusted) This common power supply DC protection board uses optocouplers. Because optocouplers are isolated from each other between input and output,Electric signal transmission has the characteristics of unidirectionality, etc., so it has good electrical insulation and anti-interference ability.In addition, since the input end of the optocoupler is a current-type low-impedance component, it has a strong common-mode rejection capability.The power supply and the sound source are separated without affecting the sound source : This protection board uses 1.6 thick 1A copper surface, double-sided tinning process, and the input voltage is DC 12V-16V or AC 12-16V : Power-on (red) indicator light is on, working indicator light is on normally, the relay is closed, if there is an impact protection board automatically adjusts the pull-in time (the relay is closed after the current passes) The power supply can be the same as the power amplifier. The negative pole of the three-channel audio source is independent. It is suitable for non-common ground and BTL circuit power amplifiers: the terminal is 7.62 pitch, and the 1/2W metal film exceeds the standard using internal resistance. The reduction is designed for high current : Joint venture Songle relay as a core component is not afraid of contact ignition and oxidation, and has a non-destructive transmission of soundNote: There is no delay when the protection board is turned on and off within 15 seconds (the first time it is turned on-after turning off, there will be a delay after 15 seconds when it is turned on)