mpc82g516a Megawin Technology, mpc82g516a Datasheet - Page 116

• Manufacturer Part Number: mpc82g516a
• Description: 8-bit Microcontroller
• Manufacturer: Megawin Technology

23.2 Brownout Detection
The brownout detection function determines if the power supply voltage falls below a certain level. The default
operation for a brownout detection is to cause the power-fail flag to be set, which can then generate an interrupt if
the Brownout interrupt (#12 in Table 19-1) is enabled. However, it may alternatively be configured to cause a
hardware reset by enabling the related hardware option.
There are two kinds of brownout detection:
(1) VDD power-fail detection: When power supplied to the VDD pin falls below V
(2) LDO power-fail detection: When the LDO output power falls below V
Note: See
Note that during power-up, the power-fail flags OPF and CPF are set by hardware owing to the power ever lower
than 3.7V and 2.4V, respectively. The user should clear them by software before a normal brownout detection.
The flags OPF and CPF may trigger a brownout interrupt if EA is set and EOPFI or EOPCI is set (Refer to
Section 19: Interrupt
To trigger an internal reset when brownout occurs, the hardware option ENLVRO or ENLVRC should be enabled.
(Refer to
The EVRCR register contains the flags and control bits for brownout detection.
EVRCR (Address=97H, EVR Control Register, Reset Value=00xx,0000B (or 0011,0000B after Power-On Reset))
EOPFI: Set/clear to enable/disable the interrupt when OPF=1.
ECPFI: Set/clear to enable/disable the interrupt when CPF=1.
OPF: VDD Power-Fail flag. This bit is set by hardware when the power supplied to the VDD pin falls below 3.7V.
It can only be cleared by software.
CPF: LDO Power-Fail flag. This bit is set by hardware when the LDO output power falls below 2.4V. It can only
be cleared by software.
PMUOFF: Set to turn off the Power Monitor Unit to save power consumption while power monitoring function is
not used.
Note all the reserved bits in this register must be kept ‘0’.
MEGAWIN
EOPFI
set by hardware to indicate a VDD power-fail condition. The detection is used in a 5V or wide-range system.
hardware to indicate an LDO power-fail condition. The detection is used in a 3.3V system.
7
Section 25: MCU’s Hardware
Section 27.1
ECPFI
6
System).
OPF
for 3.3V, 5V or wide-range system.
5
CPF
4
Option).
MPC82G516A Data Sheet
PMUOFF
3
(Reserved) (Reserved) (Reserved)
2
1
CPF
(2.4V), the CPF flag will be set by
0
OPF
(3.7V), the OPF flag will be
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