Post History
I have an mcu pin and I want to sense a voltage up to 24V to 36V. I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be...
#10: Post edited
by
Lorenzo Donati
·
2023-08-10T11:21:44Z (9 months ago)
Retagged.
#9: Post edited
by
DeadMouse
·
2023-06-15T18:49:10Z (11 months ago)
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- Note: voltage below 8.2V is considered as "input is floating".
This is the truth table- | Selection | Voltage | Floating | Ground |
- |-----------|---------|----------|--------|
- |Option 1| LOW | HIGH | HIGH |
- |Option 2| HIGH | HIGH | LOW |
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- 
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- Note: voltage below 8.2V is considered as "input is floating".
- This is the truth table.
- For simplicity we will asume that voltage means +24V DC
- | Selection | Voltage | Floating | Ground |
- |-----------|---------|----------|--------|
- |Option 1| LOW | HIGH | HIGH |
- |Option 2| HIGH | HIGH | LOW |
#8: Post edited
by
DeadMouse
·
2023-06-15T18:45:19Z (11 months ago)
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- 
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- This is the truth table
- | Selection | Voltage | Floating | Ground |
- |-----------|---------|----------|--------|
- |Option 1| LOW | HIGH | HIGH |
- |Option 2| HIGH | HIGH | LOW |
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- 
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- Note: voltage below 8.2V is considered as "input is floating".
- This is the truth table
- | Selection | Voltage | Floating | Ground |
- |-----------|---------|----------|--------|
- |Option 1| LOW | HIGH | HIGH |
- |Option 2| HIGH | HIGH | LOW |
#7: Post edited
by
DeadMouse
·
2023-06-15T18:43:40Z (11 months ago)
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- This is the truth table
- | Selection | Voltage | Floating | Ground |
- |-----------|---------|----------|--------|
- |Option 1| LOW | HIGH | HIGH |
- |Option 2| HIGH | HIGH | LOW |
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- 
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- This is the truth table
- | Selection | Voltage | Floating | Ground |
- |-----------|---------|----------|--------|
- |Option 1| LOW | HIGH | HIGH |
- |Option 2| HIGH | HIGH | LOW |
#6: Post edited
by
DeadMouse
·
2023-06-15T18:40:07Z (11 months ago)
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- 
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
HIGH: For any voltage above 8.2V or when the line is floating.
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- 
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- This is the truth table
- | Selection | Voltage | Floating | Ground |
- |-----------|---------|----------|--------|
- |Option 1| LOW | HIGH | HIGH |
- |Option 2| HIGH | HIGH | LOW |
#5: Post edited
by
DeadMouse
·
2023-06-15T18:36:55Z (11 months ago)
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
https://i.imgur.com/nCW7NuQ.png- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- 
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
#4: Post edited
by
DeadMouse
·
2023-06-15T17:06:02Z (11 months ago)
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
Anyway, to be able to connect an mcu to a high voltage I'm using a simple level translator.- This can be done with a simple NPN.
- https://i.imgur.com/nCW7NuQ.png
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Example below:
- To be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- https://i.imgur.com/nCW7NuQ.png
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
#3: Post edited
by
DeadMouse
·
2023-06-15T17:05:31Z (11 months ago)
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail).- Anyway, to be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- https://i.imgur.com/nCW7NuQ.png
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail). For this reason, I want to provide some selections like switches or jumpers to give the ability in the circuit to be modified.
- Anyway, to be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- https://i.imgur.com/nCW7NuQ.png
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
#2: Post edited
by
DeadMouse
·
2023-06-15T17:02:40Z (11 months ago)
I have an mcu pin and I want to sense a voltage up to 24V to 36V.- This can be done with a simple NPN.
- https://i.imgur.com/nCW7NuQ.png
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
- I have an mcu pin and I want to sense a voltage up to 24V to 36V.
- I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be open collector outputs.
- Also, some outputs will be just relays and the other terminal will be at GND or just at the main voltage (supply rail).
- Anyway, to be able to connect an mcu to a high voltage I'm using a simple level translator.
- This can be done with a simple NPN.
- https://i.imgur.com/nCW7NuQ.png
- This circuit gives me the following output:
- LOW: For any voltage above 8.2V
- HIGH: When the line is floating or when the line is grounded.
- I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following:
- LOW: When the line is grounded.
- HIGH: For any voltage above 8.2V or when the line is floating.
#1: Initial revision
by
DeadMouse
·
2023-06-15T16:59:42Z (11 months ago)
How to change the polarity of an input using a single switch?
I have an mcu pin and I want to sense a voltage up to 24V to 36V. This can be done with a simple NPN. https://i.imgur.com/nCW7NuQ.png This circuit gives me the following output: LOW: For any voltage above 8.2V HIGH: When the line is floating or when the line is grounded. I want to add a switch or a jumper to modify this circuit on the fly and change its behaviour as following: LOW: When the line is grounded. HIGH: For any voltage above 8.2V or when the line is floating.