PIC18F86K90-I/PT Microchip Technology, PIC18F86K90-I/PT Datasheet - Page 402

• Manufacturer Part Number: PIC18F86K90-I/PT
• Description: 64kB Flash, 4kB RAM, 1kB EE, 16MIPS, NanoWatt XLP, LCD, 5V 80 TQFP 12x12x1mm TRA
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F86K90-I/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 64MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 69
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 24x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TQFP
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC18F87K90 FAMILY
FIGURE 26-3:
26.5
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, Figure 26-4 shows a
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.
DS39957B-page 402
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
A
and T
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 26-4:
V
V
A
B
Legend:
HLVDIF Cleared in Software
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
T
A
V
V
HLVD
HLVD
T
B