SDM-IO is a stable ultrasonic range sensor and measures the distance accurately which provides 0 - 1500mm non-contact measurement function, the ranging accuracy can reach to 3mm.
Its performance is comparable with SRF05/SRF02 ultrasonic distance measuring module, also it has non-blind spot (From 0-1cm the measurement results are not accurate when we test, but more than 1cm are accurate) design and fast response.
- Supply voltage 3.8 - 5.5 V
- Global Current Consumption 8 mA
- Ultrasonic Frequency 40k Hz
- Maximal Range 1500 mm
- Minimal Range 0 cm
- Resolution 3 mm
- Trigger Pulse Width 10 μs
- Sensor Angle 15 degrees
- Outline Dimension 37x20x15 mm
There are 4 pins out of the module : VCC , Trig, Echo, GND . So itís a very easy interface for controller to use it ranging.
The all process is : pull the Trig pin to high level for more than 10us impulse, the module starts 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. So we can calculated the distance easily as in:
Test distance = (time * High speed of sound (340M / S)) / 2