Preliminary User’s Manual U19014EJ1V0UD
435
CHAPTER 17 LOW-VOLTAGE DETECTOR
17.1 Functions of Low-Voltage Detector
The low-voltage detector (LVI) has the following functions.
•
Compares supply voltage (V
DD
) and detection voltage (V
LVI
), and generates an internal interrupt signal or
internal reset signal when V
DD
< V
LVI
. Detection levels (2 levels) of supply voltage can be changed by software.
When the low-voltage detector is used to reset, bit 0 (LVIRF) of the reset control flag register (RESF) is set to 1 if
reset occurs. For details of RESF, see
CHAPTER 15 RESET FUNCTION
.
17.2 Configuration of Low-Voltage Detector
The block diagram of the low-voltage detector is shown in Figure 17-1.
Figure 17-1. Block Diagram of Low-Voltage Detector
LVIS0
LVION
−
+
Reference
voltage
source
V
DD
Internal bus
N-ch
Low-voltage detection level
selection register (LVIS)
Low-voltage detection register
(LVIM)
LVIF
INTLVI
Internal reset signal
LVIMD
V
DD
Low-voltage detection
level selector
Selector
electronic components distributor