GD32W51x User Manual
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than the specified threshold (2.4V). The VLVD is enabled by setting the VLVDEN bit in
PMU_CTL0 register, and VLVDF bit, which in the PMU_CS0 register, indicates if V
DDA
is
higher or lower than the specified threshold (2.4V). This event is internally connected to the
EXTI line 18 and can generate an interrupt if it is enabled through the EXTI registers. VLVDF
interrupt signal depends on EXTI line 18 rising or falling edge configuration.
Generally, digital circuits are powered by V
DD
, while most of analog circuits are powered by
V
DDA
. To improve the ADC conversion accuracy, the independent power supply V
DDA
is
implemented to achieve better performance of analog circuits. V
DDA
can be externally
connected to V
DD
through the external filtering circuit that avoids noise on V
DDA
, and V
SSA
should be connected to V
SS
through the specific circuit independently.
5.3.3.
1.2V power domain
The main functions that include Cortex
®
-M33 logic, AHB / APB peripherals, the APB interfaces
for the Backup domain and the V
DD
/ V
DDA
domain, etc, are located in this power domain. Once
the 1.2V is powered up, the POR will generate a reset sequence on the 1.2V
power domain.
If need to enter the expected power saving mode, the associated control bits must be
configured. Then, once a WFI (Wait for Interrupt) or WFE (Wait for Event) instruction is
executed, the device will enter an expected power saving mode which will be discussed in
the following section.
CORE_MEM1/2/3 domain
In GD32W51x, the CORE_MEM1/2/3 power domain is defined for 64KB SRAM1 / 128KB
SRAM2 / 192KB SRAM3 respectively. When run / sleep / deep-sleep mode, the SRAMs can
power-off. The typical work state is as follows:
1. Power off when standby mode / BKP_ONLY mode.
2. Power on (default) when cotrolled by register in run / sleep / deep_sleep mode.
3. Power off when controlled by register in run / sleep / deep_sleep mode.
Wi-Fi_OFF domain
Refer to Wi-Fi spec. The typical work state is as follows:
1. Power off when standby mode / BKP_ONLY mode.
2. Power on when cotrolled by register in run / sleep / deep_sleep mode.
3. Power off (default) when controlled by register in run / sleep / deep_sleep mode.
Note:
BKP_ONLY mode: Enter when V
DD
pin cut off by external Power switch, while the V
BAT
pin
supply.