weird start up issue
Posted: Sun Sep 11, 2016 11:28 am
Got a good topic for this forum.
I mentioned some distress talking about my new surround system when I was unable to get sound out and had no way to check the light pipe audio feed.
After some trial and error I got it to make sound by unplugging are replugging the 5V power cord at the processor.
It turns out, if I use the outlet strip to apply AC power to the wall wart PS (probably SMPS), the surround processor lock up... All input LEDs on. OTOH if I apply the 5V after the external PS is stabilized by plugging into the 5V jack it boots up and works.
Many microprocessors connect their reset line to the +v and have enough delay built in that the PS stabilizes before anything bad happens. I suspect this external 5V supply has an unacceptable turn on profile, or is faulty.
I guess if I didn't understand how stuff works, I would just return it for another one that doesn't work (unless it's a rogue PS).
JR
I mentioned some distress talking about my new surround system when I was unable to get sound out and had no way to check the light pipe audio feed.
After some trial and error I got it to make sound by unplugging are replugging the 5V power cord at the processor.
It turns out, if I use the outlet strip to apply AC power to the wall wart PS (probably SMPS), the surround processor lock up... All input LEDs on. OTOH if I apply the 5V after the external PS is stabilized by plugging into the 5V jack it boots up and works.
Many microprocessors connect their reset line to the +v and have enough delay built in that the PS stabilizes before anything bad happens. I suspect this external 5V supply has an unacceptable turn on profile, or is faulty.
I guess if I didn't understand how stuff works, I would just return it for another one that doesn't work (unless it's a rogue PS).
JR