CHAPTER 11 POWER-ON-CLEAR CIRCUITS
User’s Manual U14826EJ5V0UD
127
(2) Low-voltage
detection register 1 (LVIF1)
LVIF1 controls the operation of the LVI circuit.
This register is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input clears this register to 00H.
Figure 11-4. Format of Low-Voltage Detection Register 1
Symbol
<7>
6 5 4 3 2 1
<0>
Address
After
reset
R/W
LVIF1
LVION1
0 0 0 0 0 0
LVF10
FFDEH
00H
R/W
Note
LVION1
LVI operation enable flag
0
LVI
disabled
1
LVI
enabled
LVF10
LVI output detection flag
0
Power supply voltage (V
DD
) > LVI detection voltage (V
LVI
) or operation disabled
1
V
DD
< V
LVI
Note
Bit 0 is read only.
(3) Low-voltage detection level selection register 1 (LVIS1)
LVIS1 selects the level of the detection voltage (V
LVI
).
This register is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input clears this register to 00H.
Figure 11-5. Format of Low-Voltage Detection Level Selection Register 1
Symbol
7 6 5 4 3
<2>
<1>
<0>
Address
After
reset
R/W
LVIS1
0 0 0 0 0
LVS12
LVS11
LVS10
FFDFH
00H
R/W
LVS12
LVS11
LVS10
Selection of detection voltage (V
LVI
) level
Note
0 0 0
V
LVI0
0 0 1
V
LVI1
0 1 0
V
LVI2
0 1 1
V
LVI3
1 0 0
V
LVI4
1 0 1
V
LVI5
1 1 0
V
LVI6
1 1 1
V
LVI7
Note
See
CHAPTER 20 ELECTRICAL SPECIFICATIONS
for detection voltage specifications.
Caution When changing the detection voltage level (V
LVI
), an operation stabilization time of about 2
ms is required in order for the LVI output to stabilize. Do not, therefore, set the LVI circuit
to operation-enable until the operation has stabilized.