Техническая Спецификация для Microchip Technology DV164136

 2007-2012 Microchip Technology Inc.

DS39778E-page 7

This document contains device-specific information for
the following devices:

This family introduces a line of low-voltage, general
purpose microcontrollers with the main traditional
advantage of all PIC18 microcontrollers, namely, high
computational performance and a rich feature set at an
extremely competitive price point. These features
make the PIC18F87J11 family a logical choice for
many high-performance applications, where an
extended peripheral feature set is required, and cost is
a primary consideration.

1.1.1

TECHNOLOGY

All of the devices in the PIC18F87J11 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 oscilla-
tor, 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 PIC18F87J11 family offer four
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.

• An internal oscillator block which provides an 

8 MHz clock and an INTRC source (approximately 
31 kHz, stable over temperature and V

DD

). 

The oscillator block also provides a range of 
6 user-selectable clock frequencies, between 
125 kHz to 4 MHz, for a total of 8 clock
 frequencies. This option frees an oscillator pin for 
use as an additional general purpose I/O.

• A Phase Lock Loop (PLL) frequency multiplier, 

available to all of the oscillator modes, which 
allows a wide range of clock speeds from 16 MHz 
to 40 MHz

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

EXPANDED MEMORY

The PIC18F87J11 family provides ample room for
application code, from 64 Kbytes to 128 Kbytes of code
space. The Flash cells for program memory are rated
to last up to 10,000 erase/write cycles. Data retention
without refresh is conservatively estimated to be
greater than 20 years.
The Flash program memory is readable, writable, and
during normal operation, the PIC18F87J11 family also
provides plenty of room for dynamic application data,
with up to 3904 bytes of data RAM.

1.1.4

EXTERNAL MEMORY BUS

In the event that 128 Kbytes of memory are inadequate
for an application, the 80-pin members of the
PIC18F87J11 family also implement an External Mem-
ory Bus (EMB). This allows the controller’s internal
Program Counter (PC) to address a memory space of
up to 2 Mbytes, permitting a level of data access that
few 8-bit devices can claim. This allows additional
memory options, including:
• Using combinations of on-chip and external 

memory up to the 2-Mbyte limit

• Using external Flash memory for reprogrammable 

application code or large data tables

• Using external RAM devices for storing large 

amounts of variable data

1.1.5

EXTENDED INSTRUCTION SET

The PIC18F87J11 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’.

• PIC18F66J11

• PIC18F86J11

• PIC18F66J16

• PIC18F86J16

• PIC18F67J11

• PIC18F87J11