spacer spacer spacer spacer

relay with timer and thermistor

Post ReplyPost New Topic
< Prev Topic Next Topic >
Member - Posts: 22
Member spacespace
Joined: July 06, 2013
Posted: July 28, 2015 at 8:03 AM / IP Logged Link to Post Post Reply Quote toyotaguy
I picked this back up after a year on the shelf... It's prototyped and works fine on the breadboard. The only problem is that I am sometimes able to hang the ATtiny if I switch the ACC pin on and off numerous successive times in a random and rapid way. In other words I can get the MCU to freeze with the pin (PB4 in the diagram) still set HIGH. (Q1 and T3 closed). The scope detects the pin change but the MCU doesn't respond. This should never happen in normal use and I'm not sure I could duplicate it using a real key and ignition switch, but I don't like that it is possible. The only way to recover is to reset or disconnect the battery.
I have included no other components on the power supply apart from the required caps and a diode. If you think it would be advisable to add anything else (e.g., varistor, inductor, etc.) what would you add and what value? I am attempting to minimize part count and cost but if it's prudent, then it's prudent.
relay with timer and thermistor - Page 3 - Last Post -- posted image.
Page of 3

If you wish to post a reply to this topic, you must first login.
If you are not already registered, you must first register.

  Printable version Printable version Post ReplyPost New Topic
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

Follow Follow on Facebook
Friday, December 1, 2023 • Copyright © 1999-2023, All Rights Reserved Privacy Policy & Use of Cookies
Disclaimer: *All information on this site ( ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

Secured by Sectigo spacer spacer spacer
Top spacer spacer