How can I use the AM18x5 RTC to control the low-power state of an MCU?
The AM18X5 enables a variety of system implementations in which the AM18X5 can
control power usage by other elements in the system. We recommand using a Vss Power Switched, in which the internal power switch of the AM18X5 is used to completely turn off the MCU and/or other system elements.
In this case the PSW/nIRQ2 output is configured to generate the SLEEP function. Under normal circumstances, the PSW/nIRQ2 pin is pulled to VSS with approximately 1 Ω of resistance, so that the MCU receives full power. When the AM18X5 enters the SLEEP state the PSW/nIRQ2 pin is opened and power is
completely removed from the MCU.
How to make Am18x5 exit sleep state?
- By AM18x5 internal countdown timer setting
Through this way, the application can control the power consumption periodically.
- By AM18x5 Ext1 Input Interrupt
Through this way, the application can exit sleep state and resume the power supply when a valid Ext1 interrupt is detected, such as when a button input occurs, etc.