PIC16F639 Microchip Technology Inc., PIC16F639 Datasheet - Page 89

• Manufacturer Part Number: PIC16F639
• Description: 8/14-pin Flash-based, 8-bit Cmos Microcontrollers With Nanowatt Technology
• Manufacturer: Microchip Technology Inc.

8.0
The Programmable Low-Voltage Detect (PLVD)
module is a power supply detector which monitors the
internal power supply. This module is typically used in
key fobs and other devices, where certain actions
need to be taken as a result of a falling battery voltage.
FIGURE 8-1:
FIGURE 8-2:
© 2007 Microchip Technology Inc.
LVDEN
V
DD
PROGRAMMABLE
LOW-VOLTAGE DETECT
(PLVD) MODULE
LVDIF
PLVD BLOCK DIAGRAM
PLVD OPERATION
V
DD
PLVD Trip Point
Set by
Hardware
8 Stages
Reference
Generator
Voltage
PIC12F635/PIC16F636/639
The PLVD module includes the following capabilities:
• Eight programmable trip points
• Interrupt on falling V
• Stable reference indication
• Operation during Sleep
A Block diagram of the PLVD module is shown in
Figure 8-1.
Analog MUX
LVDL<2:0>
8-to-1
0
1
2
6
7
Cleared by
Software
-
+
DD
det
DS41232D-page 87
LVDIF