RCWL-1655 (JSN-SR04T) Ultrasonic Distance Measurement Module

Waterproof ultrasonic sensor operating in the range from 20 cm to 600 cm. Powered by 3 to 5V. The output is a signal whose duration is proportional to the measured distance. The sensor is compatible with the popular HC-SR04 sensor, which means that the sample programs and libraries will work correctly for both sensors.

• Wide voltage operation: 3V-5.5V
• Fully compatible with JSN-SR04T software and hardware dimensions
• Detection distance:
• @5V: 20cm - 600cm 
• @3.3V: 20cm - 400cm 
• communication protocols supported: GPIO, UART, I2C and 1-Wire

How is the sensor designed?
The sensor can be an additional accessory for robots, toys, measuring systems and other electronic and mechanized devices. An ultrasonic transmitter and receiver are located on a small sensor head. The ultrasonic wave coming from the on-board generator output is sent from the sensor and reflected from the object against which the distance is measured. The distance of the sensor from the obstacle is calculated based on the time between sending and receiving the ultrasonic wave sent from the sensor.

Sensor cooperation with single-chip computers
The sensor was designed specifically for cooperation with embedded systems, which also include popular single-chip minicomputers. The measurement is performed with an accuracy of 1 mm, which is sufficient for hobby applications and prototypes of professional measuring devices.

There are 4 pins on the module: VCC , Trig, Echo, and GND . To use the sensor: pull the Trig pin to high level for more than 10us to trigger an impulse. The module will begin sending ultrasonic pulses. If an object is detected in front of the sensor the Echo pin will rise to a logic high level. The distance between the sensor and the object can then be calculated using the following equation:

test distance = (high level time × velocity of sound (340m/s) / 2

where:

test distance - measured distance
high level time - duration of high state
velocity of sound - speed of sound wave propagation in air - 340 m/s

In short, to get the result in cm you can use the formula:

distance [cm] = ( high level time [us] * 34 ) / 1000 / 2

Technical data:

Pulse width output: serial port output
Working voltage: DC: 3.0-5.5v
Working current: less than 8mA
Probe frequency: 40KHz
Max range: 600cm
Min range: 20cm
Long range accuracy: ± 1cm
Resolution: 1 mm
Measuring angle: 75 degrees
Input trigger signal: 1, more than 10us TTL pulse, 2, serial port send command 0x55
Output echo signal: output pulse width level signal, or TTL
Wiring mode: 3-5.5v (positive pole of power supply). Trig Rx. Echo TX. GND (negative pole of power supply)
Product size: l42 * W29 * H12 mm
Working temperature: - 20 ℃ - + 70 ℃