Mk. III graphic

User's Guide


Buy Robots!
View Cart



Mark III Robot Store

Devantech SRF08 High Performance Ultrasonic Range Finder


Click for larger image
The SRF08 is a high performance sensor that uses sonar to detect objects. It has a much wider field-of-view than the Sharp infrared distance measuring sensors. Interfaces easily with the Mark III or your own robot design. Comes completely assembled - this is not a kit.

The SRF08 is an evolutionary step from the SRF04 developed to improve on the following features of the SRF04. The key points are:

  1. The SRF08 has twice the range of the SRF04, increased from 3m to 6m.
  2. The SRF04 has a long, 36mS timeout followed by a 10mS recharge time. The SRF08 doesn't have this deadtime.
  3. The SRF04 requires 2 I/O pins per sonar, wth 32 I/O lines needed for a 16 sonar system. The SRF08 is read out over an I²C bus, which requires just two lines total to address up to 16 sonars.
  4. The SRF08 does all pulse timing internally, freeing the host processor from performing this task. This simplifies the software and allows more efficient use of processor resources (e.g., processor timers or capture/counter input pins do not need to be wasted).
  5. The SRF08 consumes significantly less power, 15mA vs. 50mA for the SRF04. The SRF08 also has a 3mA standby state which is entered automatically after each ranging is performed.
  6. The SRF08 can detect up to 16 returning echoes, if several objects are at different distances within the field of view. The SRF04 only detects the first echo (nearest object).
  7. The SRF08 has a light sensor which can be read out over the I²C bus.

This item can be connected directly to a USB port on your computer using the optional USB to I2C Interface Module.

This product is made by Devantech. More information, applications, and code samples may be found on their web site.

An optional SRF08 Mounting Bracket is also available.

In Stock


Voltage: 5V only Required
Current: 15 mA Typical, 3 mA Standby
Frequency: 40 KHz
Maximum Range: 6 meters (~20 ft.)
Minimum Range: 3 cm (~1")
Max Analog Gain: Variable 94 to 1025 in 32 steps
Connection: Standard I²C Bus
Light Sensor: Front facing light sensor
Timing: Fully timed echo, freeing host controller of task
Echo: Multiple echo - keeps looking after first echo
Units: Range reported in uS, mm, or inches
Size: 1.69 x 0.79 x 0.67 in.
43 x 20 x 17 mm