9V 12V battery anti-over-discharge sound and light alarm anti-over-discharge protection board low-voltage/under-voltage protecti

I. Scope of application of this module: Mainly used for battery (9V or 12V) voltage monitoring, simple and practical, with sound and light alarm prompt. II. Product Functions: Battery under voltage after the buzzer issued a "drop drop" sound, while the red LED indicator lights up, when the battery voltage from back to the set value above, the buzzer stop alarm. II. Brief description: 1. Size: 3.0cm long * 2.9cm wide * 1.4cm high Fixed hole spacing: 2.2cm Fixed hole diameter: 3MM 2. Main chip: LM358; 9V battery: when the battery is over-discharged (battery voltage is lower than 8V or so), the red indicator lights up and the buzzer calls to realize the acoustooptic alarm, so as to realize the control of the discharge state of the battery, to prevent the battery from excessive discharge and damage the battery; 12V battery: when the battery is over-discharged (battery voltage is lower than 10.4V or so), the red indicator lights up and the buzzer calls to realize the acoustooptic alarm, so as to realize the control of the discharge state of the battery, to prevent the battery from excessive discharge and damage the battery; Three advantages and characteristics: 1, with sound and light alarm, there is no protection directly clear; 2, module input with reverse protection, input power polarity reverse connection will not burn out. But there is no overvoltage protection, and if the input exceeds 15V, the chip above the module will burn out.