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Maximum Vpp using ICSP

Posted: Mon Nov 14, 2011 5:47 pm
by Jan Lichtenbelt
The main E-block EB006 uses Vpp=13 Volt for loading a program into a microcontroller. An other board MPLAB ICD2 or 3 does have Vpp = 12 Volt.
However in datasheet of e.g. PIC16F1825 there is a warning that Vpp of 12 Volt from the MPLAP is to high and should be lowered to 9Volt.

Up to now I used the EB006 board with succes to program often 16F1825 and equivalents. Burn down of a microcontroller on the testing board is no problem, but if you have your IC on a board to use in practice, it can become a big problem.

My question is: How critical is the maximum Vpp of 9 Volt for this kind of microcontrollers?

Thanks for help.

Kind regards

Jan Lichtenbelt

----
References:
MPLAB ICD:
http://www.microchip.com/Microchip.WWW. ... =en010046#
PIC16F1825:
http://ww1.microchip.com/downloads/en/D ... 41440B.pdf
EB006 board:
http://www.matrixmultimedia.com/datashe ... 6-30-7.pdf

Re: Maximum Vpp using ICSP

Posted: Tue Nov 15, 2011 1:42 pm
by Steve
In our testing, we have not encountered a problem programming these devices with a higher Vpp. However, we will continue to monitor the issue and if it becomes a problem then we have a number of possible solutions.

Re: Maximum Vpp using ICSP

Posted: Tue Jan 24, 2012 5:26 am
by brandonb
what became of this?

Re: Maximum Vpp using ICSP

Posted: Tue Jan 24, 2012 9:38 am
by Steve
I don't think we've seen any problems so far.

Re: Maximum Vpp using ICSP

Posted: Tue Jan 24, 2012 12:54 pm
by Benj
Nope no problems to report on this at the moment. Certainly no damaged chips I'm aware of.

Re: Maximum Vpp using ICSP

Posted: Tue Jan 24, 2012 2:42 pm
by medelec35
I have used both 16F1824 and 16F1827 on Eb006 with no issues what so ever.
I guess with EB006 the current is limited to a save value, rather then direct connection to 14V minus 1.2V across bridge rectifier?

However when used with an external programmer, without ant external components these chips do get damaged. So I just use a resistor and zener diode in series to drop the voltage to a safe level.


Martin

Re: Maximum Vpp using ICSP

Posted: Tue Jan 24, 2012 6:09 pm
by brandonb
thanks guys, so on my new pcb programmer board im making with the pickit2 i shouldnt have any issues with 13.5v vpp for any 8 bit chip in 20,28,40 pin configuration, i was gonna do the same as what martin suggested with a series resistor and switch to allow zener to ground on chip side of resistor to the safe level.... i dont see how this could effect the slew rate like microchip claims, i do see it taking a few micro seconds to stablize from 13.5 to 9v, i dont think microchip envisioned the datasheet circuit for the pickit2

Re: Maximum Vpp using ICSP

Posted: Tue Jan 24, 2012 6:28 pm
by Benj
Hello,

Will the PICkit 2 program these devices? I seem to remember seeing MPLAB saying that PICkit 2 didn't support them.

The PICkit 3 ICSP header is exactly the same anyway so if you cannot using the PICkit 2 then the 3 will work.

Re: Maximum Vpp using ICSP

Posted: Thu Feb 09, 2012 8:54 pm
by Dorsdorf
Hello all.
I have PICkit2 and it works fine with these devices. Just need update the Device File up to 1.62.14 version.
Please see link below. But for PICkit2 need some additional elements for decrease Vpp voltage...

http://www.microchip.com/stellent/idcpl ... e=en027813