SRF04 Datasheet and Specifications PDF

]--------------------------------------------' ' This program uses the Devantech SRF04 to measure the distance between the ' unit and a target. Display is raw value, centimeters, and inches. ' -----[ .

w w w .D at aS he et 1 For a Javelin Stamp application note see 4U Parallax, Inc.
* Devantech SRF04 Ultrasonic Range Finder (#28015)
* 10/2003 .c om Page 1
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* Voltage
* 5 v Current
* 30 mA Typ. 50mA Max. Frequency
* 40 kHz Ma.

w w w .D at aS he et 4U .c om .

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SRF04 - Ultra-Sonic Ranger Technical Specification This project started after I looked at the Polaroid Ultrasonic Ranging module. It has a number of disadvantages for use in small robots etc. 1. 2. 3.

The SRF04 will send out an 8 cycle burst of ultrasound at 40khz and raise its echo line high. It then listens for an echo, and as soon as it detects one it lowers the echo line again. The echo line is therefore a pulse whose width is proportional to the distance to the object. By timing the pulse i.