Datasheet

CHAPTER 22 LOW-VOLTAGE DETECTOR
User’s Manual U18698EJ1V0UD
486
22.2 Configuration of Low-Voltage Detector
The block diagram of the low-voltage detector is shown in Figure 22-1.
Figure 22-1. Block Diagram of Low-Voltage Detector
LVIS1 LVIS0
LVION
−
+
Reference
voltage
source
VDD
Internal bus
N-ch
Low-voltage detection level
selection register (LVIS)
Low-voltage detection register
(LVIM)
LVIS2 LVIS3
LVIF
INTLVI
Internal reset signal
4
LVISEL
EXLVI/P120/
INTP0
LVIMD
VDD
Low-voltage detection
level selector
Selector
Selector
22.3 Registers Controlling Low-Voltage Detector
The low-voltage detector is controlled by the following registers.
• Low-voltage detection register (LVIM)
• Low-voltage detection level selection register (LVIS)
• Port mode register 12 (PM12)
(1) Low-voltage detection register (LVIM)
This register sets low-voltage detection and the operation mode.
This register can be set by a 1-bit or 8-bit memory manipulation instruction.
The generation of a reset signal other than an LVI reset clears this register to 00H.