Devantech SRF05 Ultrasonic Sensor Rangefinder up to 4m 40KHz Frequency 43x20x17mm Single Pin for Trigger/Echo or 2 Pin SRF04 compatible

Ultrasonic sensor

Range - 1cm to 4m.
Power supply - 5V, 4mA type.
Frequency - 40KHz.
Gröe - 43mm x 20mm x 17mm.

There are two operating modes available, single pin for trigger/echo or 2 pin SRF04 compatible.

The input trigger is one 10uS min smaller. TTL level pulse
Echo Pulse is a positive TTL level signal whose width is proportional to the object range.

>The SRF05 is an evolutionary step from the SRF04 and is designed to increase flexibility, increase range and further reduce cost. This makes the SRF05 fully compatible with the SRF04, increasing the range from 3 meters to 4 meters. A new mode (mode pin to ground binding) allows the SRF05 to use a single pin for trigger and echo, saving valuable pins on your controller. When the mode pin is not connected, the SRF05 operates with separate trigger and echo pins, like the SRF04. The SRF05 incorporates a small delay before the echo pulse to give slower controls such as the base stamp and picaxe time to execute their pulse in commands.

Mode 1 - SRF04 compatible - Separate trigger and echo separately
This mode uses separate trigger and echo pins and is the simplest mode. All code examples for the SRF04 work in this mode for the SRF05. To use this mode, simply leave the mode pin unconnected - the SRF05 has an internal pull-up resistor on this pin.

Mode 2 - Single pin for trigger and echo
This mode uses a single pin for trigger and echo signals and is designed to save valuable pins on embedded controllers. To use this mode, connect the mode pin to the 0V ground pin. The echo signal is displayed on the same pin as the trigger signal. The SRF05 increases the echo line only after 700uS after the end of the trigger signal. You have so much time to rotate the trigger pen and turn it into an input and have your pulse measurement code ready. The PULSIN command found on many common controllers does this automatically.