Datasheet

PIC18F2220/2320/4220/4320
DS39599G-page 232 © 2007 Microchip Technology Inc.
FIGURE 22-2: LOW-VOLTAGE DETECT (LVD) BLOCK DIAGRAM
The LVD module has an additional feature that allows
the user to supply the sense voltage to the module
from an external source. This mode is enabled when
bits LVDL3:LVDL0 are set to ‘1111’. In this state, the
comparator input is multiplexed from the external input
pin, LVDIN (Figure 22-3). This gives users flexibility
because it allows them to configure the Low-Voltage
Detect interrupt to occur at any voltage in the valid
operating range.
FIGURE 22-3: LOW-VOLTAGE DETECT (LVD) WITH EXTERNAL INPUT BLOCK DIAGRAM
LVDIF
VDD
16-to-1 MUX
LVDEN
LVD Control
Register
Internally Generated
Reference Voltage
LVDIN
1.2V
LVD
EN
LVD Control
16-to-1 MUX
BGAP
BODEN
LVDEN
VxEN
LVDIN
Register
V
DD
VDD
Externally Generated
Trip Point