Passive automatic flushing control device

The utility model discloses a passive automatic flushing control device, which comprises a core module, wherein the core module is connected with a power module, an execution module, a transmitter module and a receiving module (5); the power module is connected with the execution module; the transmitter module is communicated with the receiving module; the core module adopts the low-voltage and high-performance CMOS 8 bit chip AT89C2051 which is produced by the ATMEL company in America; and the AT89C2051 chip sends out square-wave pulse signals with certain frequency to control a light emitting diode of the transmitter module to give out light interruptedly, and meanwhile detects the signals of the receiving module to control the execution module to execute corresponding actions. The passive automatic flushing control device has the advantages of strong anti-interference ability, effective control for sensitivity, simplicity in peripheral circuit, wide range of application, low cost and the like.