Breaking News
Design How-To

The case for stand-alone reset timers in mobile devices

NO RATINGS
Page 1 / 4 Next >
More Related Links
View Comments: Newest First | Oldest First | Threaded View
old account Frank Eory
User Rank
Rookie
re: The case for stand-alone reset timers in mobile devices
old account Frank Eory   12/22/2010 8:08:18 PM
NO RATINGS
Doesn't every PMIC include a robust, software-proof watchdog timer reset function? Do some mobile handset designers really allocate PCB space for a separate watchdog IC? Why?

Forma
User Rank
Rookie
re: The case for stand-alone reset timers in mobile devices
Forma   12/22/2010 5:04:36 PM
NO RATINGS
The concept isn't new - there are already reset/watchdog ic chips often used in such designs. They allow communication with the Application processor to set-up a timer, whilst also providing protection for the SoC by holding the reset until the power is stable. It's know for years so above sounds more like a reminder than 'innovation'..

Andrewier
User Rank
Freelancer
re: The case for stand-alone reset timers in mobile devices
Andrewier   12/21/2010 12:57:20 AM
NO RATINGS
Ahnnnn... A real (I mean not software) switch, anyone? After some really strong design and debuging, of course.

Code Monkey
User Rank
Rookie
re: The case for stand-alone reset timers in mobile devices
Code Monkey   12/20/2010 4:28:57 PM
NO RATINGS
The last handheld device I worked on had an FPGA. Software was expected to detect the "power" button after 3 seconds to provide the usual graceful shutdown, but for safety we put in logic to shut off power if the user holds down the button for more than 5 seconds. It's hard to imagine phone designers leaving out such a failsafe feature. Especially since Microsoft has conditioned users to expect a "reset button".

sharps_eng
User Rank
Rookie
re: The case for stand-alone reset timers in mobile devices
sharps_eng   12/11/2010 11:17:06 PM
NO RATINGS
I always scroll to the last page to check the writer's byline: ahah, its a Fairchild guy selling chips. Fair enough, but some of his fixit examples are just fixing terribly bad design in the original smartphones, ie the white screen of death; having to remove the battery... seems they never learn. I hereby declare that my preference is for a separate watchdog device, but I'd use an on-chip device provided it was independent of everything except the power rails. (I am assuming we are not talking about hi-rel devices here by the way.)

Flash Poll
Radio
LATEST ARCHIVED BROADCAST
Join our online Radio Show on Friday 11th July starting at 2:00pm Eastern, when EETimes editor of all things fun and interesting, Max Maxfield, and embedded systems expert, Jack Ganssle, will debate as to just what is, and is not, and embedded system.
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Times on Twitter
EE Times Twitter Feed
Top Comments of the Week