Hello,
I am trying to develop a system with CAN communication using a PIC18F25K80.
The PIC is working good with CAN, however I have a problem...
When I turn OFF the system power I would like to keep the PIC alive for 1 or 2 seconds to be able to send CAN messages to turn OFF another module.
So, basically my system is powered by 12 Volts and I have a 78L05 to feed the PIC with 5 Volts.
My idea is to use ADC or Interrupt flag in the PIC to check when the power is turned OFF.
When this happens, I must have power to send CAN messages for 1 or 2 seconds. These CAN messages will inform other modules that the system was turned OFF.
I measured the current consumption on my system and I have 36mA.
I think I could use a capacitor and a diode. However the capacitor needed is big and expensive.
Do you know any other method ?
Thank you for your help.
I am trying to develop a system with CAN communication using a PIC18F25K80.
The PIC is working good with CAN, however I have a problem...
When I turn OFF the system power I would like to keep the PIC alive for 1 or 2 seconds to be able to send CAN messages to turn OFF another module.
So, basically my system is powered by 12 Volts and I have a 78L05 to feed the PIC with 5 Volts.
My idea is to use ADC or Interrupt flag in the PIC to check when the power is turned OFF.
When this happens, I must have power to send CAN messages for 1 or 2 seconds. These CAN messages will inform other modules that the system was turned OFF.
I measured the current consumption on my system and I have 36mA.
I think I could use a capacitor and a diode. However the capacitor needed is big and expensive.
Do you know any other method ?
Thank you for your help.