TAS5630B output protection relay


2012-12-09 2:19 pm
hi all

i have built an amp around the TAS5630B which works fine and have good sound quality..

for added safety for the speakers and to suppress popping noises i put an output relais on the board.

when i switch on, the following sequenz is done (+50V are already applied)

1) reset is opened, (square wave) amp is starting
2) audio signal is switched on
3) output relay is switched on

between these steps is always about 500msecs

switching off is done simultaneously

my qestion now: when i switch off under heavy load(loud music) can the inductance of the speaker create a voltage spike over the relay contacts-and possibly destroy the TAS5630B?

if so, i will implement a power down sequence, eg. reset close and audio off, after 100msec open the speaker protection relay

please chime in

thank you

Last edited:


2012-02-11 11:43 am

as I am designing a multi-channel system around the TAS5630 right now, I would reall be interested in your protection board.
Could you possibily provide your schematics?

Theoretically, this should be impossible. I just don't know how to describe :$ In my opinion, the 50V supply is too low to create dangerous spikes. But I dont know for sure. Please do not rely on my answer :(
A power-down sequence is never a bad idea :)



2012-12-09 2:19 pm
Isn't the 5630 protected enough itself?

you are right, the chip is a very good protected design..

but if the current gets a chance, however, to break through the silicon insulation, you will have DC across the speaker..

i know, its not very likely, and this will be the worst of the worst cases, but..better safe than sorry



i have changed design to also make a power down sequence..


2010-02-12 4:09 pm
Does the TAS5630 need a preamp for anything other than volume control ?

I have been running it with a pre, but well, I do need volume control. I mean can it handle line level input ?

Also has anyone tried those gain switches. I have it set to the lowest in all 4. Of course I also am running it on a dinky little 30v .5 amp power supply.
Its needing to be made a bit more robust before I go playing with those dip switches I think.