Very strange behaviour of ATtiny13A

Log in or register to post comments
Go To Last Post
9 posts / 0 new
Author
Message
sq5rix
sq5rix's picture
Level: Rookie
Joined: Mon. Feb 16, 2015
Posts: 29 View posts
#1
Posted by sq5rix: Sun. Apr 19, 2015 - 04:49 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi folks!

 

I have a PCB I made to host a tiny 13A

 

I have a bizarre situation, I think it is some initialisation problem, or fuses. Please help !!

 

When I upload my program (assembler in Studio) I get nice 6uA in sleep (8 seconds, woken up by Watchdog.

 

This is good, the board is powered from LiPo cell.

 

However, when I cycle power, the multimeter shows 230 uA

 

I have no idea what reason :( Reset is pulled up to Vcc with 4.7kOhm, no other resistive load, all ports are only woken up when needed. Comparator  is off, ADC is used only momentarily, every hour. 

 

There is one button with internal pull-up, connected to the GND, normally open, no current there.

 

Have you evere experienced such funny behaviour?

Greetings, Tom

Tags:

AVR Microcontrollers, megaAVR and tinyAVR
Last Edited: Sun. Apr 19, 2015 - 05:23 PM
Top
Gold Markclawson
clawson's picture
Level: Moderator
Joined: Mon. Jul 18, 2005
Posts: 102882 View posts
Location: (using avr-gcc in) Finchingfield, Essex, England
Posted by clawson: Sun. Apr 19, 2015 - 05:20 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Do we get to see the code? Or is this one of those fun guessing games? 

Top
sq5rix
sq5rix's picture
Level: Rookie
Joined: Mon. Feb 16, 2015
Posts: 29 View posts
Posted by sq5rix: Sun. Apr 19, 2015 - 05:46 PM (Reply to #2)
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Yeah, you are right.

 

Here you go: https://www.assembla.com/code/sq...

 

hf.asm is the main file

 

Greetings, Tom

Last Edited: Sun. Apr 19, 2015 - 05:47 PM
Top
sq5rix
sq5rix's picture
Level: Rookie
Joined: Mon. Feb 16, 2015
Posts: 29 View posts
Posted by sq5rix: Sun. Apr 19, 2015 - 06:13 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Uh, sorry friends !!!!

 

I found the culprit. Probably the tiny was malfunctioning, I took a fresh one and it is 6uA all the way :)

 

Good lesson :)

Greetings, Tom

Top
Torby
Torby's picture
Level: 10k+ Postman
Joined: Tue. Nov 11, 2003
Posts: 10389 View posts
Location: Bartlesville Oklahoma USA
Posted by Torby: Sun. Apr 19, 2015 - 06:38 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Also, set up the brown-out-detector. If the power rises too slowly from a brown out situation, the processor might not start properly. The "BOD" will solve this.

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

Top
sq5rix
sq5rix's picture
Level: Rookie
Joined: Mon. Feb 16, 2015
Posts: 29 View posts
Posted by sq5rix: Sun. Apr 19, 2015 - 07:05 PM (Reply to #5)
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Thanks, indeed I have. It is set for 2.8V, but I use BODCR to put it to sleep every time the processor sleep. After waking up, it is on automatically. Vcc was over 4V all time.
I think I killed it will zillions of DW fuse changes when I went rampant debugging the beast :)

Greetings, Tom

Top
sq5rix
sq5rix's picture
Level: Rookie
Joined: Mon. Feb 16, 2015
Posts: 29 View posts
Posted by sq5rix: Mon. Apr 20, 2015 - 01:22 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi again!
I have recreated the error :)
I powered the board from LiPo cell, 3.7V - 4V read back by Atmel ICE.
Normally, all was ok - I could debug and go back to ISP programming
However, when I added a multimeter to measure the current, the power was insufficient for correct operation. I got 0x0c error.
When I powered directly, the situation was corrected and back to normal. The chip lives on :)
Good luck!

Greetings, Tom

Last Edited: Mon. Apr 20, 2015 - 01:23 PM
Top
Bronze Markjs
js's picture
Level: Moderator
Joined: Wed. Mar 28, 2001
Posts: 30657 View posts
Location: Sydney, Australia (Gum trees, Koalas and Kangaroos, No Edelweis, but plenty of Corona beer)
Posted by js: Mon. Apr 20, 2015 - 10:35 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

when I added a multimeter to measure the current,

In SERIES of course.... How much voltage does your meter drop? Do you have another meter to measure this?

 

And of course you MUST have bypass caps or inserting the meter in series with VCC will cause havoc.

 

John Samperi

Ampertronics Pty. Ltd.

https://www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

Top
sq5rix
sq5rix's picture
Level: Rookie
Joined: Mon. Feb 16, 2015
Posts: 29 View posts
Posted by sq5rix: Mon. Apr 20, 2015 - 10:41 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hmm, I simply put it in series battery -> meter -> Vcc
I will try to measure the drop, however I have no idea about bypass caps. Of course I have two at the battery connector and two on Vcc pin.
I will read more about power consumption measurements :)

Greetings, Tom

Last Edited: Mon. Apr 20, 2015 - 11:07 PM
Top