Microchip Technology AC244045 Data Sheet

© 2009 Microchip Technology Inc.

DS41341E-page 195

ICSP™ programming allows customers to manufacture
circuit boards with unprogrammed devices. Programming
can be done after the assembly process allowing the
device to be programmed with the most recent firmware
or a custom firmware. Five pins are needed for ICSP™
programming:

• ICSPCLK

• ICSPDAT

• MCLR/V

PP

• V

DD

• V

SS

The device is placed into Program/Verify mode by
holding the ICSPCLK and ICSPDAT pins low then
raising the voltage on MCLR/V

PP

 from 0v to V

PP

. In

Program/Verify mode the Program Memory, User IDs
and the Configuration Words are programmed through
serial communications. The ICSPDAT pin is a
bidirectional I/O used for transferring the serial data and
the ISCPCLK pin is the clock input. For more information
on ICSP™ refer to the “PIC16F72x/PIC16LF72x
Programming Specification” (DS41332).

The ICD 2 produces a V

PP

 voltage greater

than the maximum V

PP

 specification of the

PIC16F72X/PIC16LF72X. When using
this programmer, an external circuit, such
as the AC164112 MPLAB ICD 2 V

PP

 volt-

age limiter, is required to keep the V

PP

voltage within the device specifications.

V

DD

V

PP

GND

External

Device to be

Data

Clock

V

DD

MCLR/V

PP

V

SS

ICSPDAT

ICSPCLK

*

*

*

To Normal Connections

*

Isolation devices (as required).

10k

Programming 
Signals

Programmed