The US-100 ultrasonic rangefinder module offers non-contact distance measurement ranging from 2 cm to 4.5 m. It operates with a wide voltage input range of 2.4V to 5.5V and consumes less than 2mA in static mode. The module features a built-in temperature sensor to correct distance readings, improving accuracy under varying environmental conditions. It supports multiple communication modes, including GPIO and UART (serial), and is equipped with a watchdog for stable and reliable performance.

Working Principle:

1. Apply a high signal (≥10μs) to the TRIG pin to trigger the sensor.
2. The module emits eight 40kHz ultrasonic pulses and waits for a signal to return.
3. If a signal returns, the ECHO pin outputs a high signal. The duration of the high signal represents the time it took for the sound wave to travel to the object and back.
4. Distance Calculation: Distance=High signal time×Speed of sound (340 m/s)2text{Distance} = frac{text{High signal time} times text{Speed of sound (340 m/s)}}{2}Distance=2High signal time×Speed of sound (340 m/s)​ The time measured by the ECHO pin is converted into distance by multiplying it by the speed of sound (340 m/s) and dividing by 2 (to account for the round-trip travel time).

Notes:

• Ensure proper mode selection before powering on to avoid incorrect operation.
• When using the serial mode, set the baud rate to 9600 for proper communication.
• The module performs best when the target is a solid object with a smooth surface, as this helps improve the accuracy of measurements.

Features:

• Operating Voltage: 2.4V to 5.5V DC
• Quiescent Current: <2mA
• Working Temperature: -20°C to +70°C
• Sensing Angle: <15°
• Detection Range: 2 cm to 450 cm
• Accuracy: ±0.3 cm + 1%
• Temperature Compensation: Built-in sensor to adjust readings based on temperature
• Output Methods: Level or UART (selectable via jumper cap)
• UART Serial Configuration: Baud rate 9600, 8 data bits, 1 stop bit, no parity, no flow control
• Size: 20mm x 45mm (module size), 15mm thickness

Applications:

• Distance Measurement: For applications requiring accurate non-contact measurement within 2 cm to 4.5 m.
• Obstacle Detection: Used in robotics, drones, and automation systems for detecting obstacles or measuring distances.
• Temperature-Compensated Sensing: Ideal for environments where temperature fluctuations affect measurement accuracy.
• Parking Sensors: Can be used in parking assistance systems or vehicle distance detection.
• Liquid Level Measurement: Suitable for monitoring liquid levels in tanks or containers.