Datasheet

 2010 Microchip Technology Inc. DS39770C-page 9
PIC18F85J90 FAMILY
1.0 DEVICE OVERVIEW
This document contains device-specific information for
the following devices:
This family combines the traditional advantages of all
PIC18 microcontrollers – namely, high computational
performance and a rich feature set – with a versatile
on-chip LCD driver, while maintaining an extremely
competitive price point. These features make the
PIC18F85J90 family a logical choice for many
high-performance applications where price is a primary
consideration.
1.1 Core Features
1.1.1 nanoWatt TECHNOLOGY
All of the devices in the PIC18F85J90 family incorporate
a range of features that can significantly reduce power
consumption during operation. Key items include:
• Alternate Run Modes: By clocking the controller
from the Timer1 source or the internal RC
oscillator, power consumption during code
execution can be reduced by as much as 90%.
• Multiple Idle Modes: The controller can also run
with its CPU core disabled but the peripherals still
active. In these states, power consumption can be
reduced even further, to as little as 4% of normal
operation requirements.
• On-the-Fly Mode Switching: The power-managed
modes are invoked by user code during operation,
allowing the user to incorporate power-saving ideas
into their application’s software design.
1.1.2 OSCILLATOR OPTIONS AND
FEATURES
All of the devices in the PIC18F85J90 family offer six
different oscillator options, allowing users a range of
choices in developing application hardware. These
include:
• Two Crystal modes, using crystals or ceramic
resonators.
• Two External Clock modes, offering the option of
a divide-by-4 clock output.
• A Phase Lock Loop (PLL) frequency multiplier,
available to the External Oscillator modes which
allows clock speeds of up to 40 MHz.
• An internal oscillator block which provides an
8 MHz clock (±2% accuracy) and an INTRC source
(approximately 31 kHz, stable over temperature
and V
DD), as well as a range of six user-selectable
clock frequencies, between 125 kHz to 4 MHz, for a
total of eight clock frequencies. This option frees the
two oscillator pins for use as additional general
purpose I/O.
The internal oscillator block provides a stable reference
source that gives the family additional features for
robust operation:
• Fail-Safe Clock Monitor: This option constantly
monitors the main clock source against a reference
signal provided by the internal oscillator. If a clock
failure occurs, the controller is switched to the
internal oscillator, allowing for continued low-speed
operation or a safe application shutdown.
• Two-Speed Start-up: This option allows the
internal oscillator to serve as the clock source
from Power-on Reset, or wake-up from Sleep
mode, until the primary clock source is available.
1.1.3 MEMORY OPTIONS
The PIC18F85J90 family provides a range of program
memory options, from 8 Kbytes to 32 Kbytes of code
space. The Flash cells for program memory are rated
to last up to 1000 erase/write cycles. Data retention
without refresh is conservatively estimated to be
greater than 20 years.
The PIC18F85J90 family also provides plenty of room
for dynamic application data, with up to 2048 bytes of
data RAM.
1.1.4 EXTENDED INSTRUCTION SET
The PIC18F85J90 family implements the optional
extension to the PIC18 instruction set, adding 8 new
instructions and an Indexed Addressing mode.
Enabled as a device configuration option, the extension
has been specifically designed to optimize re-entrant
application code originally developed in high-level
languages, such as ‘C’.
1.1.5 EASY MIGRATION
Regardless of the memory size, all devices share the
same rich set of peripherals, allowing for a smooth
migration path as applications grow and evolve.
The consistent pinout scheme used throughout the
entire family also aids in migrating to the next larger
device. This is true when moving between the 64-pin
members, between the 80-pin members, or even
jumping from 64-pin to 80-pin devices.
The PIC18F85J90 family is also largely pin compatible
with other PIC18 families, such as the PIC18F8720 and
PIC18F8722, as well as the PIC18F8490 family of
microcontrollers with LCD drivers. This allows a new
dimension to the evolution of applications, allowing
developers to select different price points within
Microchip’s PIC18 portfolio, while maintaining a similar
feature set.
• PIC18F63J90 • PIC18F83J90
• PIC18F64J90 • PIC18F84J90
• PIC18F65J90 • PIC18F85J90