Infrared transmitter circuit composed of 555 time base circuit

Shown is an infrared transmitter circuit composed of a 555 time base circuit . The 555 time base integrated circuit in the circuit constitutes a multivibrator. Since isolation diodes Doi and D are set up in the charge and discharge circuit, the charge and discharge circuit can be adjusted independently, so that the duty cycle of the circuit output pulse reaches 1:10. This helps to increase the peak current of the infrared light-emitting diode and increase the emission power. The pulse signal output by the @ pin of the 555 time base is added to the base of the transistor Qi through R3, and Q. drives the infrared light-emitting diode Dm to work. As long as the button switch K is pressed once, the circuit can emit infrared rays. The operating distance is 5 to 8 m.