Hi all,
I am starting my first battery powered project and of course I would like to keep the battery running as long as possible. To do that I obviously need to minimize the power consumption. The application is a basic temperature reading. Every 5 minutes or so is good enough.
I ran a bunch of tests and this is what I found:
Once I enter sleep mode,
- I did verify that the current sunk by RA0 is indeed < 200nA
- But the total current used by the PIC is around 2µA @ 2.5v
So here is my question: how do I reduce these 2µA?
Before going through the obvious, let me add this:
- I am using a small test board. Only RA0 is connected.
- All ports are configured as digital output
- I checked that on reset (and in conformity with the datasheet)
- RB weak pull ups are disabled
- the comparator modules are disabled
- the ADC is disabled
- Timer1 and 2 are disabled
- The CCP module i disabled
- The serial port is disabled
- The SSP module is disabled
So what did I forget? How do I get to a sub 1 μA system as the AN879 from microchip states: "A typical smoke detector or Tire Pressure Monitoring (TPM) system with sub 1 μA current consumption can be achieved"
Thank you all. Any suggestion will be welcome.
I am starting my first battery powered project and of course I would like to keep the battery running as long as possible. To do that I obviously need to minimize the power consumption. The application is a basic temperature reading. Every 5 minutes or so is good enough.
I ran a bunch of tests and this is what I found:
Once I enter sleep mode,
- I did verify that the current sunk by RA0 is indeed < 200nA
- But the total current used by the PIC is around 2µA @ 2.5v
So here is my question: how do I reduce these 2µA?
Before going through the obvious, let me add this:
- I am using a small test board. Only RA0 is connected.
- All ports are configured as digital output
- I checked that on reset (and in conformity with the datasheet)
- RB weak pull ups are disabled
- the comparator modules are disabled
- the ADC is disabled
- Timer1 and 2 are disabled
- The CCP module i disabled
- The serial port is disabled
- The SSP module is disabled
So what did I forget? How do I get to a sub 1 μA system as the AN879 from microchip states: "A typical smoke detector or Tire Pressure Monitoring (TPM) system with sub 1 μA current consumption can be achieved"
Thank you all. Any suggestion will be welcome.