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2010 Microchip Technology Inc. DS39592F-page 1
PIC18FX220/X320
1.0 DEVICE OVERVIEW
This document includes the programming specifications
for the following devices:
• PIC18F1220
• PIC18F1320
• PIC18F2220
• PIC18F2320
• PIC18F4220
• PIC18F4320
2.0 PROGRAMMING OVERVIEW
These devices can be programmed using the high-
voltage In-Circuit Serial Programming
TM
(ICSP
TM
)
method, or the low-voltage ICSP method, both while in
the user’s system. The low-voltage ICSP method is
slightly different than the high-voltage method and
these differences are noted where applicable. This
programming specification applies to these devices in
all package types.
2.1 Hardware Requirements
In High-Voltage ICSP mode, these devices require 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 “AC/DC
Characteristics” for additional hardware parameters.
2.1.1 LOW-VOLTAGE ICSP
PROGRAMMING
In Low-Voltage ICSP mode, these devices can be pro-
grammed 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
“AC/DC Characteristics” for additional hardware
parameters.
2.1.2 VDD POWER SUPPLY
It is recommended that the power supply decoupling
capacitance be added at the programmer socket.
Capacitance in the range of 0.1 F to 10 F should be
connected from V
DD to VSS, and located as close to the
programming socket as possible.
2.2 Pin Diagrams
The programming pin descriptions for these devices
are shown in Table 2-1 and the pin diagrams are shown
in Figure 2-1 through Figure 2-6. The pin descriptions
of these diagrams do not represent the complete func-
tionality of the device types. Refer to the appropriate
device data sheet for complete pin descriptions.
TABLE 2-1: PIN DESCRIPTIONS (DURING PROGRAMMING)
Pin Name
During Programming
Function Pin Type Pin Description
MCLR/VPP/RA5
(2)
VPP P High-Voltage Programming Enable
V
DD VDD P Power Supply
VSS VSS PGround
RB5 PGM I Low-Voltage ICSP™ Input when LVP
Configuration bit equals ‘1’
(1)
RB6 PGC I Serial Clock
RB7 PGD I/O Serial Data
Legend: I = Input, O = Output, P = Power
Note 1: See Section 5.3 “Single-Supply ICSP Programming” for more detail.
2: RA5 is only available on the PIC18F1X20.
Flash Microcontroller Programming Specification
