I am using the HC-SR04 ultrasonic module that came with the raphael ultimate kit for raspberry pi. I looked at the tutorial from sunfounder…. They dont use any resistors? The ultrasonic module (echo) is 5V no? the pi cannot handle 5V its designed for 3.3v? Everywhere else i look and every video i watch they use resistors for a voltage divider…. why would the company that provides the module not understand how it works?!?!?! Am i missing something??? or are they just trying to fry my pi?? I dont understand how you can be this big of a company that is supplying kits/tutorials/videos…. and you dont even give the correct information??? I guess this is what happens when you buy anything from China….
The ultrasonic module is powered from the rpi’s own regulated 3v3 supply, as shown on the wiring diagram between GPIO22 and SPIMOSI. Therefore any output voltages from the ultrasonic module into the rpi are limited to that same value of 3v3.
the wiring diagram clearly shows it being powered by 5v though? and its working voltage is 5v… so the 3.3v wouldnt work? unless im missing something
Hm interesting, the diagram I recalled was this..
The modules working supply range is 3V to 5.5V, but, I share your concern about driving the rpi gpio when operating at 5v. Best await Sunfounder to clarify, sorry i couldn’t really help.
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Yea i should have been more specific, its for the python stuff ( 2.2.8 Ultrasonic Sensor Module — SunFounder Ulimate Raphael Kit for Raspberry Pi documentation )
i didnt look too closely before until you said its powered by 3.3v, but the schematic diagram actually does show it being powered by 3.3v, but for some reason the wiring diagram shows it connected to the 5v pin? I have read the working voltage is 5v, have you used this at all(with 3.3v?), im new to a lot of this so i just assumed working voltage meant what it needs, but it seems its the highest it can handle? All of that to ask, just plug it into 3.3v then and forget the resistors?
The modules working supply range is 3V to 5.5V, but, I share your concern about driving the rpi gpio when operating at 5v. Best await Sunfounder to clarify, sorry i couldn’t really help. I would not run it at 5v, but I do not know that modules maximum output voltage, so it may be safe, but I simply do not know.
You are correct. The web page that you pointed me towards does have 3v3 schematic, but 5v wiring. The web page that I pointed to, shows both as 3v3. Seems to be 2 slightly different versions.
Thank you for bringing this to our attention, and please accept our sincere apologies.
You are absolutely correct. The tutorial contains an error: the sensor should be connected to 3.3V for power, but the diagram incorrectly shows it connected to 5V.
We are very sorry for the confusion and any inconvenience this may have caused. Our team will immediately update the course materials to correct this wiring diagram.
We truly appreciate your careful review and valuable feedback, which helps us improve our resources for all users.