Q: TAS5630, Short Circuit Protection

Hi,

Could you please clarify on the short circuit protection in TAS5630DKD IC. I have been asked by the customer to short the output of this amplifier (that is, shorting the two leads of the differential output) for 24 hours and check whether the Amplifier IC is still alive.  Please advise whether this test can be done? Is there any short circuit protection provided in this IC?

 


A: Re: TAS5630, Short Circuit Protection

Hello,

The TAS5630 has a short circuit detection system for shorts between an OUT_X pin and either GND or PVDD. However, this system will not detect a short between two output pins, and it only works during startup. Please se page 23 of the TAS5630 datasheet for more information.

However, the Over current protection should detect if there is a problem at the outputs that could potentially damage the device. This will only happen if an audio signal is applied so that you are forcing two different voltages at the output, or if the switching frequencies of the two shorted outputs are out of phase. Either of these two scenarios will cause at least one channel to turn off in order to stop the high current.

Another thing to consider is the long speaker wires. If their resistance is large enough, a short might not be detected since the current will never reach the OCP threshold (and this is technically not a short since the amplifier does see some impedance in the output path). Either way the IC should protect itself if there is a large enough current that would damage it.

We have seen situations in which long speaker wires get hot when they are shorted because the amp sees a normal load and does not shut off. The solution to this is to make sure you are using thick enough wires that are rated for the desired max power.