Nations Technologies Inc.
Tel
:
+86-755-86309900
:
info@nationstech.com
Address: Nations Tower, #109 Baoshen Road, Hi-tech Park North.
Nanshan District, Shenzhen, 518057, P.R.China
34
/
631
Figure 3-2 Brown-out reset (BOR) waveform
Note: The reset temporization t
RSTTEMPO
exists only based on the BOR minimum threshold (V
BOR0
).
Programmable voltage detector (PVD)
PVD monitors the power supply by comparing the V
DD
voltage with the relevant bits in the Power Control Register
2 (PWR_CTRL2). PWR_CTRL2.PLS[2:0] select the threshold for the monitored voltage. Enable PVD by setting
PWR_CTRL2.PVDEN.
The PWR_STS2.PVDO flag is used to indicate whether the V
DD
is above/below the PVD voltage threshold. This
event is connected internally to the 16th line of the external interrupt and produces an interrupt if the interrupt is
enabled in the external interrupt register. A PVD interrupt occurs when the V
DD
drops below the PVD threshold and/or
when the V
DD
rises above the PVD threshold, according to the rise/fall edge trigger setting of the external interrupt
line 16. For example, this feature can be used to perform emergency shutdown tasks.
PVD can also be configured to monitor the external analog voltage PVD_IN (PB7) (compared to the internal
VREFINT (about 1.2V)).
VDD/VDDA
V
BOR
(
rising edge
)
RESET
V
BOR
(
falling edge
)
Temporization
t
RSTTEMPO
40mV
hysteresis