That's quite interesting. And good to know for many Microchip version of PI=
Ckit 2 users.
The cause probably is because of a component design fault on the original P=
ICkit 2 hardware, the original designer pushed the component too much to it=
s spec. boundary on Vpp circuit, so it cannot supply enough Vpp current eve=
n for some PIC chips alone. =


On Microchip Forum, there is a official=A0post about how to "Pump your Vpp =
current".

Here is part of the info:

"The VPP (programming voltage) charge pump on PICkit 2 units supplies limit=
ed current at 12 Volts. =

Older "Black Button" units can only supply about 3 mA. =

Newer "Red Button" units can supply about 6 mA. =

(The exact threshold will depend on component tolerances in a particular un=
it). =


This is sufficient to program any circuit following the ICSP guidelines in =
Chapter 3 of the PICkit 2 User's guide. (The exception being the new PIC16F=
72x parts with some Black Button units.) However, there might be situations=
 where an abnormally heavily load is present on the VPP pin, such as an old=
er board not following the ICSP design guidelines. In these situations it c=
an be very helpful to be able to supply more current from the PICkit 2 VPP =
pin. =


The PICkit 2 may be modified to supply up to about 13-15 mA at 12 Volts fro=
m VPP. This modification applies to all PICkit 2 units (Red & Black button)=
. =

To increase the charge pump current capability, replace the 3 components at=
 the following reference designators with these new components: =


R21 - replace with 0603 510 Ohm 5% Resistor =


L1 - replace with Murata LQH43MN681J03L (available from Mouser) =


C15 - replace with 68uF 10% 20V Tantalum cap, such as Kemet T491D686K020AT =
(available from Mouser) =

NOTE: If you only need 10-12mA, replacing C15 is not necessary. =


Please note that this modification is purely optional, and is posted solely=
 for information purposes for those interesting in tinkering with their PIC=
kit 2 unit. "

This modification info=A0is for Microchip version of PICkit 2 only. Au Grou=
p Electronics developed BB0703 and BB0703+ don't have this issue=A0since th=
e BB0703/BB0703+ design uses components which can provide more Vpp current=
=A0 than any of the above spec.

Funny N.
Au Group Electronics, http://www.AuElectronics.com




________________________________
From: WH Tan <whsiung.my@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
Sent: Monday, January 19, 2009 5:41:43 AM
Subject: Re: [PIC] ICSP to RJ-11

2009/1/16 Joseph Bento wrote:

> I'm having some issues with my ICD-2 that are probably of my own
> making.=A0 As a beginner, however, I think I am more comfortable with
> the PicKit2, and I need the ability to connect the PicKit2 to my
> PICDEM2 board as well as a AC162049 Universal Programming Adaptor.


Joe,

This is not directly related to your original question, but I think it
worth a mention.

If you plan to use AC162049 with PICKit 2, you have to disable the LED
on that board.=A0 This is because PICKit 2 won't be able to supply
sufficient current for the LED.=A0 The simplest way to do this is remove
the current limiting resistor.

Best regards,

-- =

WH Tan
-- =

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      =

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