2x PICKIT3 say board drawing too much current, PICKIT4 is OK

Thread Starter

AlbertHall

Joined Jun 4, 2014
12,017
I have a test board with two PIC12F1840 and very little else. Trying to program this with a PICKIT3, it syas that the board is drawing too much current, sometimes.
I tried a different PICKIT3 with similar results.
Then I tried a PICKIT4 which works reliably, programs and debugs, with no error messages.
I changed back to one of PICKIT3's and the problem returned.

The board should only be drawing the PIC supply current (32MHz internal oscillator).
Can the PICKIT4 supply more current than the PICKIT3?
Are both 3's broken?
 

nsaspook

Joined Aug 27, 2009
9,706

Thread Starter

AlbertHall

Joined Jun 4, 2014
12,017
There is nothing there to consume anywhere near 30mA.
And with the PICKIT4 it all works as it should so the chips are not damaged.
 

Thread Starter

AlbertHall

Joined Jun 4, 2014
12,017
What version of software are you running? Will it program using IPE with a lower target voltage?
I have come across that problem before so I tried it with lower voltage but still with the same result.
They didn't complain that the voltage was low, just too much current and can't program.
 

nsaspook

Joined Aug 27, 2009
9,706
I have come across that problem before so I tried it with lower voltage but still with the same result.
They didn't complain that the voltage was low, just too much current and can't program.
I've had similar problems with the P3 (I mainly use the 4 series now for new device support) when I know the current error is bogus. If you have MPLAB IDE v8.92 can you program the chip with a good HEX file?
 

Thread Starter

AlbertHall

Joined Jun 4, 2014
12,017
I've had similar problems with the P3 (I mainly use the 4 series now for new device support) when I know the current error is bogus. If you have MPLAB IDE v8.92 can you program the chip with a good HEX file?
I do have 8.92. I'll give it a go...
 
I have a test board with two PIC12F1840 and very little else. Trying to program this with a PICKIT3, it syas that the board is drawing too much current, sometimes.
I tried a different PICKIT3 with similar results.
Then I tried a PICKIT4 which works reliably, programs and debugs, with no error messages.
I changed back to one of PICKIT3's and the problem returned.

The board should only be drawing the PIC supply current (32MHz internal oscillator).
Can the PICKIT4 supply more current than the PICKIT3?
Are both 3's broken?
All PICkits behave strangely. Try increasing the supplied voltage in 0.5V steps (without exceeding the PIC max voltage) and also see the 'circuits which will prevent the debugger from functioning' section in the PICKit manuals (any components on MCLR, PGC or PGD will cause issues with PICKit 4 but a series resistor, pullup resistor and cap to ground are required on MCLR with PICkit 3). You mention there are two PICs on the board, presumably you are not trying to program both at the same time.
 

Thread Starter

AlbertHall

Joined Jun 4, 2014
12,017
The programming pins are entirely dedicated to the programmer. The PICs each have their own ICSP pins on my test board.
 

trebla

Joined Jun 29, 2019
479
I have experienced same problem with one of my old product line boards and PICkit3. This error does'nt appear within all of the boards but those failed boards i can program with PICkit2 and ICD3. Sometimes it helps if i use shorter ICSP cable and USB cable with PICkit3. On my newer boards i use Tag-connect ICSP cable and this kind of error never happened again.
 

rick.curl

Joined Jul 14, 2020
9
Do you have large bypass capacitors on your board? It could be that the programmer says the current is too high because it is having to charge the capacitors. Can you upload your schematic?

-Rick
 

trebla

Joined Jun 29, 2019
479
On my old board i use 100uF caps in my new designs i use 22uF or 47uF caps. But i have noticed that PICkit3 is very sensitive to long ICSP cable + long traces to PIC, i have'nt tested my old boards with smaller capacitors, maybe this (big capacitor) gives additional problems to PICkit3 too.
 

rick.curl

Joined Jul 14, 2020
9
FYI- I've had nothing but trouble out of the Pickit 3. BTW- I'm not the only one. Did you see the EEVblog Pickit 3 review
The funny thing about that review is that it hit a nerve with Microchip. Here is Microchip's response
I still prefer the Pickit 2 but with alternate software. Look here: PicKit PLUS It adds support for many more chips and is MUCH faster than Microchip's version.
If you look on eBay, get the Pickit 2's that are in a rectangular beige-colored box. Those things are indestructible!
 

nsaspook

Joined Aug 27, 2009
9,706
On my old board i use 100uF caps in my new designs i use 22uF or 47uF caps. But i have noticed that PICkit3 is very sensitive to long ICSP cable + long traces to PIC, i have'nt tested my old boards with smaller capacitors, maybe this (big capacitor) gives additional problems to PICkit3 too.
Long cables have caused the 'current' problem for some reason on the PK3. I normally design a ICSP header with taller than normal pins for the PK connection. Seems to work OK even with the PK3 powering some AUX circuits too.
1649615546272.png
 

atferrari

Joined Jan 6, 2004
4,593
FYI- I've had nothing but trouble out of the Pickit 3. BTW- I'm not the only one. Did you see the EEVblog Pickit 3 review
The funny thing about that review is that it hit a nerve with Microchip. Here is Microchip's response
I still prefer the Pickit 2 but with alternate software. Look here: PicKit PLUS It adds support for many more chips and is MUCH faster than Microchip's version.
If you look on eBay, get the Pickit 2's that are in a rectangular beige-colored box. Those things are indestructible!
Have you checked the date of that video?

Many things occurred after that.
 

rick.curl

Joined Jul 14, 2020
9
Have you checked the date of that video?

Many things occurred after that.
Yes- I acknowledge that, but in my opinion the pickit 3 is still kind of awkward to use. Seems like I'm endlessly downloading firmware for whatever chip I'm using. The Pickit 2 does not have to do that. I also acknowledge that the Pickit 2 cannot program as many different chips as the Pickit 3 or 4, but with the Pickit PLUS software, the list is greatly expanded.
Besides, I thought Microchip's response was hilarious. I like companies that are not afraid to laugh at themselves.

-Rick
 
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