TAS5615 only half of device being used

tbriseb

Other Parts Discussed in Thread: TAS5615, TAS5162

Hi the

I nticed that precious post (http://e2e.ti.com/support/amplifiers/audio_amplifiers/f/6/t/28843.aspx) specifies how to setp the the TAS5162 in the event only one half of the outputs are being used. I have a similar situation wtih the TAS5615 where Ionly plan on using the A&B outputs and not the C&D outputs.

Would it be safe to say that I can connect things in the same way specified in the in the above link which specifies the following:

Connect the PWM input of the unused 1/2 bridge to one of the driven PWM inputs; otherwise, the input activity detector will cause the whole device to shutdown. Then, add the bootstrap cap, BST_x to OUT_x of the unused channel. Finally, connect the PVDD_x (PVDD pin of the unused 1/2 bridge) to GND (ground). The output of the unused channel can then be left floating.

Thanks

over 14 years ago

0 David Harrison over 14 years ago

Intellectual 480 points

Just to clarify something in this post - the TAS5612 is a digital PWM input device, whereas the TAS5615 is an analog input device.

0 Aaron E. over 14 years ago in reply to David Harrison

TI__Expert 6050 points

I've asked Tuan Luu to help with this issue.

-Aaron

0 Tuan over 14 years ago in reply to David Harrison

TI__Mastermind 33420 points

Hi David:

The question: I have a similar situation with the TAS5615 where only plan on using the A&B outputs and not the C&D outputs.

In your case it is a bit different, a full bridge is not used.

For the C+D inputs, you can ground them via a cap. For the bootstraps C+D, you still need to connect them with bootstrap caps.

Best regards,

Tuan

0 Don Dapkus over 14 years ago in reply to Tuan

TI__Guru**** 189399 points

Did this answer your question?

0 David Harrison over 14 years ago in reply to Tuan

Intellectual 480 points

Tuan Luu said:

Hi David:

The question: I have a similar situation with the TAS5615 where only plan on using the A&B outputs and not the C&D outputs.

In your case it is a bit different, a full bridge is not used.

For the C+D inputs, you can ground them via a cap. For the bootstraps C+D, you still need to connect them with bootstrap caps.

Best regards,

Tuan

Tuan, could you please explain why the bootstrap capacitors are need on the unsed half bridges if their respective PVDD pins are grounded?

Also, why are the100 Ohm series resistors and the 100pF capacitors needed at the A/B input pins? Thanks.

0 Tuan over 14 years ago in reply to David Harrison

TI__Mastermind 33420 points

Hello David:

1. The PVDD_X pins are connected resistively internally to the part.

2. The 100 ohm series in conjunction with the 10uf blocking cap gives a ~10Hz HPF. The 100pF to ground is for ground reference just in case the external input does not have good grounding. The cap can be removed if the grounding is good.

Best regards,

Tuan

Audio

Audio forum

TAS5615 only half of device being used