25.6 Functional Description

The SHDWC manages the main power supply. To do so, it is supplied with VDDBU and manages wake-up input pins and one output pin, SHDN.

A typical application connects the pin SHDN to the enable input of the device's power supply circuit. The wake-up inputs (WKUPn) connect to any push-buttons or signal that wake up the system.

The software is able to control the pin SHDN by writing the Control register (SHDW_CR) with the bit SHDW at 1. The shutdown is taken into account only two SLCK cycles after the write of SHDW_CR. This register is password-protected and so the value written should contain the correct key for the command to be taken into account. As a result, the SHDN pin is driven low and the system should be powered down.