The transmitter module is based on the NE555 infrared transmitter module. 38KHz carrier circuit board produced by NE555, no MCU's PWM pins to reduce corresponding code, reducing the load on the MCU. The SIG module pin is high, the module will send an infrared signal of 38KHz, the SIG pin is low, the module will stop sending infrared signals. The infrared receiver module is based on an integrated infrared receiver head. The infrared receiver module and the transmitter module can complete the infrared remote control with codec program. It can receive the modulated infrared signal of 38KHz sent by the IR transmitter module and demodulate it to a logic level, that is, when it receives the modulated infrared signal, it outputs a negative pulse and returns to normal (high level). The infrared receiver module and the transmitter module can complete the infrared remote control with codec program. Infrared Transmitter Module: Operating Voltage: 4.5 - 5.5V DC Operating Current: 50mA (max) Emission Angle: 45 degrees SIG Pin Current: High Level 0.4mA (max), Low Level 1.4mA (max) You can manually adjust the direction of the launch tube according to actual application requirements Infrared Receiver Module: Operating Voltage: 3.0 - 5.5V DC Operating Current: 2mA (max) Receiving Angle: 90 degrees Size: 2.4x2.4cm/0.94x0.94inch Note: Please allow 1-3mm error due to manual measurement. Make sure you don't mind before bidding. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you Package Includes: 1x Infrared Transmitter Module 1x Infrared Receiver Module