
PIC18F1230/1330
2009 Microchip Technology Inc.
DS39758D-page 187
19.0
LOW-VOLTAGE DETECT (LVD)
PIC18F1230/1330 devices have a Low-Voltage
Detect module (LVD). This is a programmable circuit
that allows the user to specify the device voltage trip
point. If the device experiences an excursion past the
trip point, an interrupt flag is set. If the interrupt is
enabled, the program execution will branch to the
interrupt vector address and the software can then
respond to the interrupt.
completely controls the operation of the LVD module.
This allows the circuitry to be “turned off” by the user
under software control, which minimizes the current
consumption for the device.
The block diagram for the LVD module is shown in
REGISTER 19-1:
LVDCON: LOW-VOLTAGE DETECT CONTROL REGISTER
U-0
R-0
R/W-0
R/W-1
R/W-0
R/W-1
—
IRVST
LVDEN
LVDL3(1)
LVDL2(1)
LVDL1(1)
LVDL0(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
Unimplemented:
Read as ‘0’
bit 5
IRVST:
Internal Reference Voltage Stable Flag bit
1
= Indicates that the voltage detect logic will generate the interrupt flag at the specified voltage
trip point
0
= Indicates that the voltage detect logic will not generate the interrupt flag at the specified voltage
trip point and the LVD interrupt should not be enabled
bit 4
LVDEN:
Low-Voltage Detect Power Enable bit
1
= LVD enabled
0
= LVD disabled
bit 3-0
LVDL3:LVDL0:
Voltage Detection Limit bits(1)
1111
= Reserved
1110
= Maximum setting
.
0000
= Minimum setting
Note 1: