
2010 Microchip Technology Inc.
DS39616D-page 25
PIC18F2331/2431/4331/4431
2.0
GUIDELINES FOR GETTING
STARTED WITH PIC18F
MICROCONTROLLERS
2.1
Basic Connection Requirements
Getting started with the PIC18F2331/2431/4331/4431
family of 8-bit microcontrollers requires attention to a
minimal set of device pin connections before
proceeding with development.
The following pins must always be connected:
All VDD and VSS pins
All AVDD and AVSS pins, regardless of whether or
not the analog device features are used
MCLR pin
These pins must also be connected if they are being
used in the end application:
PGC/PGD pins used for In-Circuit Serial
Programming (ICSP) and debugging purposes
OSCI and OSCO pins when an external oscillator
source is used
Additionally, the following pins may be required:
VREF+/VREF- pins are used when external voltage
reference for analog modules is implemented
The minimum mandatory connections are shown in
FIGURE 2-1:
RECOMMENDED
MINIMUM CONNECTIONS
Note:
The AVDD and AVSS pins must always be
connected, regardless of whether any of
the analog modules are being used.
PIC18FXXXX
V
DD
V
SS
VDD
VSS
VDD
AV
DD
AV
SS
V
DD
V
SS
C1
R1
VDD
MCLR
R2
C2(1)
C3(1)
C4(1)
C5(1)
C6(1)
Key (all values are recommendations):
C1 through C6: 0.1 F, 20V ceramic
R1: 10 k
R2: 100 to 470
Note
1:
The example shown is for a PIC18F device
with five VDD/VSS and AVDD/AVSS pairs.
Other devices may have more or less pairs;
adjust the number of decoupling capacitors
appropriately.