PIC18F23K22-I/ML Microchip Technology Inc., PIC18F23K22-I/ML Datasheet - Page 346

• Manufacturer Part Number: PIC18F23K22-I/ML
• Description: 8KB, FLASH, 768BYTES-RAM, 8-BIT FAMILY, NANOWATT XLP, 28 QFN 6X6MM TUBE
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F23K22-I/ML

• A/d Inputs: 17-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 16 MIPS
• Eeprom Memory: 1K Bytes
• Input Output: 24
• Interface: I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin QFN
• Programmable Memory: 8K Bytes
• Ram Size: 512 Bytes
• Speed: 48 MHz
• Temperature Range: –40 to 125 °C
• Timers: 1-8-bit, 3-16-bit
• Voltage, Range: 1.8-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part

PIC18(L)F2X/4XK22
FIGURE 23-3:
23.5
In many applications, it is desirable to detect a drop
below, or rise above, a particular voltage threshold. For
example, the HLVD module could be periodically
enabled to detect Universal Serial Bus (USB) attach or
detach. This assumes the device is powered by a lower
voltage source than the USB when detached. An attach
would indicate a high-voltage detect from, for example,
3.3V to 5V (the voltage on USB) and vice versa for a
detach. This feature could save a design a few extra
components and an attach signal (input pin).
For general battery applications,
possible voltage curve. Over time, the device voltage
decreases. When the device voltage reaches voltage
V
The interrupt could cause the execution of an ISR,
which would allow the application to perform “house-
keeping tasks” and a controlled shutdown before the
device voltage exits the valid operating range at T
This would give the application a time window,
represented by the difference between T
safely exit.
DS41412D-page 346
A
, the HLVD logic generates an interrupt at time, T
CASE 1:
CASE 2:
Enable HLVD
Enable HLVD
Applications
HLVDIF
HLVDIF
IRVST
IRVST
V
V
DD
DD
HIGH-VOLTAGE DETECT OPERATION (VDIRMAG =
HLVDIF may not be set
Internal Reference is stable
Figure 23-4
A
and T
shows a
Internal Reference is stable
B
Preliminary
, to
T
T
IRVST
IRVST
A
B
.
.
HLVDIF cleared in software,
HLVDIF remains set since HLVD condition still exists
FIGURE 23-4:
V
V
A
B
Legend:
HLVDIF cleared in software
V
V
A
B
1
= HLVD trip point
= Minimum valid device
)
TYPICAL LOW-VOLTAGE
DETECT APPLICATION
 2010 Microchip Technology Inc.
operating voltage
Time
HLVDIF cleared in software
T
A
V
V
HLVD
HLVD
T
B