Aj Sr04m Datasheet Jun 2026

The original AJ-SR04M datasheet is not always available on major manufacturer sites (e.g., ST, TI) because it's a module. However, you can download it from:

| Parameter | Conditions | Value | |-----------|------------|-------| | Supply voltage | Absolute max | 5.5V | | Supply voltage | Operating | 4.5V – 5.5V | | Logic input low | Trig, EN | < 0.8V | | Logic input high | Trig, EN | > 2.0V (3.3V compatible) | | Echo output low | IOL = 2mA | < 0.4V | | Echo output high | IOH = 2mA | > 4.0V (5V logic) | | Output impedance | - | 100 Ω |

Why 58? Speed of sound ~343 m/s at 20°C → 1 cm travel = 29 µs round trip (out + back). So 1 µs = 1/29 cm? Wait, let's derive: aj sr04m datasheet

The AJ-SR04M has a built-in temperature compensation circuit (unlike HC-SR04). It adjusts the echo pulse width internally to approximate real distance at -15°C to +65°C within ±1%.

By following these guidelines and recommendations, developers can effectively utilize the AJ-SR04M in their projects and applications. The original AJ-SR04M datasheet is not always available

The AJ-SR04M is commonly used in:

long duration = pulseIn(ECHO, HIGH, 30000); // timeout 30ms (≈5m) if (duration == 0) Serial.println("Out of range"); else float distance = duration / 58.3; Serial.print("Distance: "); Serial.print(distance); Serial.println(" cm"); So 1 µs = 1/29 cm

duration = pulse_end - pulse_start distance = duration * 17150 # cm return round(distance, 2)

Thus:

#define TRIG 9 #define ECHO 10