Detection Circuit for Instantaneous Voltage Drop and On-Board Diagnostic system

A detection circuit for instantaneous voltage drop and an on-board diagnostic system. The detection circuit comprises two RC circuits, each of the RC circuits comprises a first resistor, a second resistor, and an energy storage capacitor; a first end of the first resistor is used for receiving a to-be-detected voltage, and a second end thereof is connected to a first end of the second resistor; the energy storage capacitor is connected in parallel with the second resistor; the first end of the second resistor forms an output end of the RC circuit, and the output end is connected to an input end of the comparator; an output end of the comparator is connected to the determination unit; in the two RC circuits, the resistance ratios of the second resistors to the first resistors are different, the capacitances of the energy storage capacitors are different.