TPA3131D2: Stereo single-end output

hello sir, 

Single-Ended Outputs

Many designs use amplifiers with single-ended outputs because they only require half as many transistors as a full-bridge output, and integrated amplifiers with single-ended outputs only require one output pin instead of two.

Single-ended amplifiers also have a few disadvantages compared to amplifiers with bridge-tied load (BTL) outputs. First, single-ended amplifiers require either split positive and negative power supplies or DC blocking capacitors. If DC blocking caps are used, they need to be large in order to prevent them from affecting the low-frequency performance of the amplifier. For example, an amplifier with an 8Ω speaker needs a 1000µf cap in order to achieve a -3dB point of 20Hz.

DC blocking caps can also cause audible pops as they charge up to Vcc/2 when the amplifier is turned on. A resistor divider from Vcc to ground can be used to charge the capacitor up to Vcc/2 at a relatively slow rate when the power is turned on, minimizing or eliminating the pop.

If the amplifier does not have feedback then PSRR might be a problem. Two DC blocking capacitors can be used to create a low-impedance AC voltage divider to improve the PSRR. If two DC blocking capacitors are used then each cap only needs to have ½ of the capacitance because the circuit sees the parallel impedance of the two capacitors.

examples attached.

Kuramochi,

The input doesn't need to be single ended.  It can be single ended or differential input. 

If differnetial. just connect differential DAC's output to 1uF of INL/P.

If single ended, connect one 1uF to GND, another connect to DAC.

Dylan

Hi Kuramochi,

The unused out, BST pins should not be floating, the BST capacitor must be mounted.

Unused input pins should be connected to ground through capacitors.

Regards,

Derek