Excelity HC-SR04 Ultrasonic Moudle is to measure the distance of object by 40KHz ultrasonic sound wave. This moulde provides 2cm-400cm non-contact measurement function, the ranging accuracy can reach to 3mm. It is great for the project that need distance measurement, such as Distometer,intelligent robot navigation system,etc.

Module main technical parameters:
-Working Voltage : 5V(DC)
-Static current: Less than 2mA
-Output signal: Electric frequency signal, high level 5V, low level 0V
-Sensor angle: Not more than 15 degrees
-Detection distance: 2cm-450cm.
-High precision: Up to 0.3cm
-Input trigger signal: 10us TTL impulse
-Echo signal : output TTL PWL signal

Pin definition:
-VCC: connect to 5V DC
-Trig(T): control pin, connect to a standard I/O port
-Echo(R):receiving end, connect to a standard I/O port
-GND: Connect to Ground

Notes:
-1. The module should be inserted in the circuit before been powered to avoid producing high level of misoperation; if producted, power it again.
-2. Before connect to VCC terminal, the GND terminal should be connected the module first,otherwise,it will affect the normal work of the module.

Module Working Principle:
-1. Pull the Trig pin to high level for more than 10us impulse, the module start ranging.
-2. The module automatically sends eight 40KHz square wave to detect whether a signal is returned.
-3. Finished ranging, If you find an object in front, Echo pin will be high level, and based on the different distance, it will take the different duration of high level.
-4. Calculated the distance, the distance = (high level time * sound velocity (340M/S) / 2.

Package included:
-3pcs HC-SR04 Moulde
-3pcs Mounting Bracket