Futura SRF05 Technical Specification

Ultra-sonic ranger

SRF05 Technical Documentation

Introduction

The SRF05 is an evolutionary step from the SRF04, and has been designed to increase flexibility, increase range, and to

reduce costs still further. As such, the SRF05 is fully compatible with the SRF04. Range is increased from 3 meters to 4

meters. A new operating mode (tying the mode pin to ground) allows the SRF05 to use a single pin for both trigger and

echo, thereby saving valuable pins on your controller. When the mode pin is left unconnected, the SRF05 operates with

separate trigger and echo pins, like the SRF04. The SRF05 includes a small delay before the echo pulse to give slower

controllers such as the Basic Stamp and Picaxe time to execute their pulse in commands.

This mode uses separate trigger and echo pins, and is the simplest mode to use. All code examples for the SRF04 will work

for the SRF05 in this mode. To use this mode, just leave the mode pin unconnected - the SRF05 has an internal pull up

resistor on this pin.

http://www.robot-electronics.co.uk/htm/srf05tech.htm (1 di 4)09/03/2007 15.41.31

SRF05 - Ultra-Sonic Ranger

Technical Specification

Table of Contents

Do you have a question about the SRF05 and is the answer not in the manual?

Page 1 This mode uses separate trigger and echo pins, and is the simplest mode to use. All code examples for the SRF04 will work for the SRF05 in this mode. To use this mode, just leave the mode pin unconnected - the SRF05 has an internal pull up resistor on this pin.
Page 2 To use this mode, connect the mode pin to the 0v Ground pin. The echo signal will appear on the same pin as the trigger signal. The SRF05 will not raise the echo line until 700uS after the end of the trigger signal. You have that long to turn the trigger pin around and make it an input and to have your pulse measuring code ready.
Page 3 The SRF05 Timing diagrams are shown above for each mode. You only need to supply a short 10uS pulse to the trigger input to start the ranging. The SRF05 will send out an 8 cycle burst of ultrasound at 40khz and raise its echo line high (or trigger line in mode 2).
Page 4 SRF05 Technical Documentation that I'm aware of. The beam pattern of the SRF05 is conical with the width of the beam being a function of the surface area of the transducers and is fixed. The beam pattern of the transducers used on the SRF05, taken from the manufacturers data sheet, is shown below.