Timeline for Circuit to convert voltages from 3.3 V and 1.5 V to 3V3 logic levels
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Mar 20, 2023 at 1:21 | comment | added | jjcasmar | I didn't say I have 3.3V at the pin. I said that when the led is on, it is 3.3V at the pin, and the RPi reads True, but when the led is off, the pin is at 1.5 V (3.3V - LED drop), and the RPi still reads True | |
| Mar 20, 2023 at 1:20 | comment | added | MikroPower | @user253751 - With the Pi4 I had the problem, this did not work with WiringPi. He is using the RPi3, so this should be not a problem. Possibly he have accidentally activated the pullup. | |
| Mar 20, 2023 at 1:15 | comment | added | Criticizing Israel not allowed | @MikroPower then make it a pull-down instead? | |
| Mar 20, 2023 at 1:11 | comment | added | MikroPower | This will not work. Simply because he said that he have 3.3V at the pin. +3.3V---LED---pin---resistor---GND , this means that the internal pullup of the RPI is activated and your transistor would be always activated. Normally the voltage would be 3.3V-U_LED=1.5V or 0V. So he have the RPi pullup-problem. | |
| Mar 20, 2023 at 1:08 | comment | added | jjcasmar | I am not completely sure I understand your circuit. I am adding a circuit to mine in case it was not clear | |
| Mar 20, 2023 at 1:02 | history | answered | Spehro 'speff' Pefhany | CC BY-SA 4.0 |