SLASEG6B May 2018 – June 2020 TAS3251
The TAS3251 supports synchronizing the internal oscillator and output switching frequency of multiple TAS3251 devices for managing the power supply, electro-magnetic interference and preventing audio beating. For slave mode operation, turn off the oscillator of the slave by pulling the FREQ_ADJ pin to DVDD. This configures the OSC_IOM and OSC_IOP pins as inputs to be slaved from an external differential clock. In a master/slave system inter-channel delay is automatically added to the PWM between audio channels, which can be seen with all channels switching at different times. This will not influence the audio output, but only the switch timing to minimize noise coupling between audio channels through the power supply. Inter-channel delay is needed to optimize audio performance and to get better operating conditions for the power supply. The inter-channel delay will be set up for a slave device depending on the polarity of the OSC_IOM and OSC_IOP connection as follows:
Multiple slaves can be connected to one master TAS3251. If more than 2 slaves are used it is best to alternate the slave modes so that adjacent devices are configured in different slave modes. The inter-channel delay for interleaved channel idle switching is given in the table below for the master/slave and output configuration modes in degrees relative to the PWM frame.
|Master||MODE = 0, 2 x BTL mode||MODE = 1, 1 x PBTL mode|