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2010 Microchip Technology Inc. DS30500B-page 1
PIC18F2331/2431/4331/4431
1.0 DEVICE OVERVIEW
This document includes the programming specifications
for the following devices:
• PIC18F2331
• PIC18F2431
• PIC18F4331
• PIC18F4431
2.0 PROGRAMMING OVERVIEW
OF THE PIC18FXX31
PIC18FXX31 devices can be programmed using either
the high voltage In-Circuit Serial Programming
TM
(ICSP
TM
) method, or the low voltage ICSP method.
Both of these can be done with the device in the users’
system. The low voltage ICSP method is slightly differ-
ent than the high voltage method, and these differ-
ences are noted where applicable. This programming
specification applies to PIC18FXX31 devices in all
package types.
2.1 Hardware Requirements
In High Voltage ICSP mode, the PIC18FXX31 requires
two programmable power supplies: one for V
DD and
one for MCLR
/VPP. Both supplies should have a
minimum resolution of 0.25V. Refer to Section 6.0 for
additional hardware parameters.
2.1.1 LOW VOLTAGE ICSP
PROGRAMMING
In Low Voltage ICSP mode, the PIC18FXX31 can be
programmed using a V
DD source in the operating
range. This only means that MCLR
/VPP does not have
to be brought to a different voltage but can instead be
left at the normal operating voltage. Refer to
Section 6.0 for additional hardware parameters.
2.2 Pin Diagrams
The pin diagrams for the PIC18FXX31 family are
shown in Figure 2-1, Figure 2-2, and Figure 2-3. The
pin descriptions of these diagrams do not represent the
complete functionality of the device types. Users
should refer to the appropriate device data sheet for
complete pin descriptions.
TABLE 2-1: PIN DESCRIPTIONS (DURING PROGRAMMING): PIC18FXX31
Pin Name
During Programming
Pin Name Pin Type Pin Description
MCLR
/VPP VPP P Programming Enable
V
DD
(2)
VDD P Power Supply
V
SS
(2)
VSS P Ground
AV
DD AVDD P Analog Power Supply
AVSS AVSS P Analog Ground
RB5 PGM I Low Voltage ICSP™ Input when LVP
Configuration bit equals ‘1’
(1)
RB6 SCLK I Serial Clock
RB7 SDATA I/O Serial Data
Legend: I = Input, O = Output, P = Power
Note 1: See Section 5.3 for more detail.
2: All power supply and ground must be connected, including AVDD and AVSS.
Flash Microcontroller Programming Specification
