I'm trying to use an ultrasonic sensor with a Raspberry Pi. The ultrasonic sensor's echo is 5V, but the Raspberry Pi's GPIO pins can only handle 3.3V inputs. I ended up getting an 8 channel logic level converter to convert the 5V signal to 3.3V since I have three ultrasonic sensors I need to do this for and wanted to avoid a mess of resistors.
I believe I have set everything up correctly, but I am unable to get the 5V echo to convert into a 3.3V signal. I have verified that the ultrasonic sensor is working. If I skip the voltage conversion and allow the 5V echo to go straight to the GPIO pin, I can see the distance is being measured correctly.
I created a diagram showing my current approach. The ultrasonic is connected to ground and a 5V power. It receives a 3.3V trigger signal and provides a 5V echo signal. The 5V echo signal goes to B2 and should be coming out A2.
I tried connecting OE to 3.3V, 5V, and ground, but none of those combinations work. I have also verified that the A side is supposed to be receiving the lower voltage and the B side is supposed to be receiving the higher voltage.
Example wiring for bidirectional 3.3V to 5V conversion: VA: 3.3V power + VB: 5V power + GND: Ground (-) from the two power supplies (3.3V and 5V power supplies ) A1 to 3.3V pin (such as from Raspberry Pi) B1 to 5V pin (such as from Arduino) When A1 has a high 3.3V signal, B1 will output the same signal at 5V and when B1 has a high 5V input, A1 will output the same signal at 3.3V ( No direction control required because this product is bidirectional! )
Additionally, I found this post which seemed relevant, but I'm not very familiar with electronics and wasn't sure if the issue in that question was the same.
I would really appreciate any advice. Thanks!