FreezeIo issue | Cypress Semiconductor
I have a low power application that is drawing too much current when connected to another IC and placed into Deep Sleep.
If I measure current of each IC independently, the micro is drawing 19uA and the other IC 8uA when in deep sleep.
If I have both powered together (even though the interface pins are not active), the current jumps by additional 50uA.
When I issue CySysPmFreezeIo() before deep cleep, the current drops right down below 19uA with both ICs connected. But, the circuit does not operate correctly and if I attempt to debug then I loose coms with MiniProg 3 when freezing the IO.
It appears when the the IO is frozen, it now longer gets woken from Deep Sleep (I am using an IO pin to wake from sleep).
I copied the IO freeze example from the PSCOC4200 GPIO document.
Do I need to add a delay or something after Unfreeze before using the pins?
Also, I have set the IO pins to High Impedance Digital for inputs and Pull Down Resistive for outputs, I assume this is the lowest current option ?
BTW: I am not worried about powered up current as it only operates for less than 100ms and back to sleep, it is the deep sleep current I want to reduce.