Hi all,
I have two questions about connecting sensors to the Flex-Full Board.
1) I have a sensor which has got an output 0-5V. Which is the best way to connect it to the Flex which has got the Vref levels 0-3.3V ?
2) I have another sensor which has three pins +12V, OUT (0-5V), GND. From the Flex I have only the possibility to have 3.3V or 5V as output power supply. If I use an external power supply for the sensor I think I\'ll lose the ground reference and than I won\'t have a correct measure from the sensor ? How could I solve it ?
Thanks in advance,
Pasquale.
Flex+Sensors
Moderator: paolo.gai
Re:Flex+Sensors
Hi Pasquale!
About the following one:
ciao,
PJ
About the following one:
check the pins you want to connect on the dspic datasheet. Most of the dsPIC pins accept a 5V input...1) I have a sensor which has got an output 0-5V. Which is the best way to connect it to the Flex which has got the Vref levels 0-3.3V ?
ciao,
PJ
-
desmomito
Re:Flex+Sensors
Hi,
I\'ve checked. The problem is the only digital input pins can accept 5V. Unfortunatly not analog input pins.
Any order informatiot about my post ?
Thank you,
Pasquale.
I\'ve checked. The problem is the only digital input pins can accept 5V. Unfortunatly not analog input pins.
Any order informatiot about my post ?
Thank you,
Pasquale.
-
nino
Re:Flex+Sensors
You\'re right, analog inputs accept only voltages in the 0-3V3 range.
The faster solution is a couple of resistors in order to do a partition. Better solutions are possible with buffers, OA with gain set to 2/3 and so on... It depends from your sensor.
The faster solution is a couple of resistors in order to do a partition. Better solutions are possible with buffers, OA with gain set to 2/3 and so on... It depends from your sensor.
-
desmomito
Re:Flex+Sensors
Thank you very much. What about the second one :
2) I have another sensor which has three pins +12V, OUT (0-5V), GND. From the Flex I have only the possibility to have 3.3V or 5V as output power supply. If I use an external power supply for the sensor I think I\'ll lose the ground reference and than I won\'t have a correct measure from the sensor ?
2) I have another sensor which has three pins +12V, OUT (0-5V), GND. From the Flex I have only the possibility to have 3.3V or 5V as output power supply. If I use an external power supply for the sensor I think I\'ll lose the ground reference and than I won\'t have a correct measure from the sensor ?
-
nino
Re:Flex+Sensors
You have 2 possibilities:
[ol]
[*]You use an external 12V power supply and connect the 2 Ground.
[*]You power the Flex board with a 12V supply and use the Vout line for the sensor power supply.
[/ol]
Thr first one is better in term of quality, while the second one is easier because it uses only 1 powre supply.
[ol]
[*]You use an external 12V power supply and connect the 2 Ground.
[*]You power the Flex board with a 12V supply and use the Vout line for the sensor power supply.
[/ol]
Thr first one is better in term of quality, while the second one is easier because it uses only 1 powre supply.
-
desmomito
Re:Flex+Sensors
Thank you for your advices. I have one more question :
- What\'s the difference between GND_OUT and GND ? I\'m using for the sensors which needs power supply 3.3V and 5V the GND as ground reference. For the sensor which needs 12V if I use the second method that you\'ve written : Could I use the Vout and GND or I have to use V_OUT and GND_OUT ? Will I loose something because the references af the ADC are 3.3V and GND ?
Thank you in advance,
Pasquale.
- What\'s the difference between GND_OUT and GND ? I\'m using for the sensors which needs power supply 3.3V and 5V the GND as ground reference. For the sensor which needs 12V if I use the second method that you\'ve written : Could I use the Vout and GND or I have to use V_OUT and GND_OUT ? Will I loose something because the references af the ADC are 3.3V and GND ?
Thank you in advance,
Pasquale.