Section 19 Band-Gap Circuit, Power-On Reset, and Low-Voltage Detection Circuits
19.2.2
Low-Voltage-Detection Status Register (LVDSR)
LVDSR indicates whether the power-supply voltage falls below or rises above the respective
given values.
Initial
Bit
Bit Name Value
R/W
Description
7 to 2
All 1
Reserved
These bits are always read as 1 and cannot be modified.
LVD Power-Supply Voltage Fall Flag
[Setting condition]
1
0
LVDDF
0*
R/W
R/W
•
When the power-supply voltage falls below Vint (D)
(Typ. = 3.7 V)
[Clearing condition]
When writing 0 to this bit after reading it as 1
•
LVDUF
0*
LVD Power-Supply Voltage Rise Flag
[Setting condition]
•
When the power supply voltage falls below Vint (D)
while the LVDUE bit in LVDCR is set to 1 and then
rises above Vint (U) (Typ. = 4.0 V) before falling
below Vreset1 (Typ. = 2.3 V)
[Clearing condition]
When writing 0 to this bit after reading it as 1
•
Note:
*
Initialized by an LVDR.
Rev. 3.00 Sep. 10, 2007 Page 384 of 528
REJ09B0216-0300