PIC18F25J11-I/PT MICROCHIP [Microchip Technology], PIC18F25J11-I/PT Datasheet - Page 371

• Manufacturer Part Number: PIC18F25J11-I/PT
• Description: 28/44-Pin, Low-Power, High-Performance Microcontrollers with nanoWatt XLP Technology
• Manufacturer: MICROCHIP [Microchip Technology]

FIGURE 23-3:
23.5
In many applications, it is desirable to have the ability to
detect a drop below, or rise above, a particular threshold.
For general battery applications, Figure 23-4 provides a
possible voltage curve.
Over time, the device voltage decreases. When the
device voltage reaches voltage, V
generates an interrupt at time, T
cause the execution of an ISR, which would allow the
application to perform “housekeeping tasks” and
perform a controlled shutdown before the device
voltage exits the valid operating range at T
The HLVD, thus, would give the application a time
window, represented by the difference between T
T
© 2009 Microchip Technology Inc.
B
, to safely exit.
CASE 1:
CASE 2:
Enable HLVD
Enable HLVD
Applications
IRVST
LVDIF
IRVST
LVDIF
V
V
DD
DD
HIGH-VOLTAGE DETECT OPERATION (VDIRMAG =
LVDIF may not be set
Internal Reference is stable
A
. The interrupt could
A
, the HLVD logic
B
.
A
Internal Reference is stable
and
T
T
IRVST
IRVST
PIC18F46J11 FAMILY
LVDIF cleared in software,
LVDIF remains set since HLVD condition still exists
FIGURE 23-4:
V
V
A
B
Legend:
LVDIF cleared in software
V
V
1
A
B
)
= HLVD trip point
= Minimum valid device
TYPICAL HIGH/
LOW-VOLTAGE DETECT
APPLICATION
operating voltage
Time
LVDIF cleared in software
T
A
V
V
DS39932C-page 371
HLVD
HLVD
T
B