Audio

Audio forum

State Resolved
Locked Locked
Replies 12 replies
Subscribers 29 subscribers
Views 1505 views
Users 0 members are here

Support feedback

Options

Options

Similar topics

Can I use the LM4838 as mono audio amp?

Hidetoshi Matsunami

Expert 2750 points

Other Parts Discussed in Thread: LM4838

Hello Team,

I'd like to ask you about LM4838(stereo audio amp).

Can I use the LM4838 as mono audio amp?

Also could you tell me the application note which has the reference circuit of mono configuration if you have it?

Best Regards,

Hidetoshi Matsunami

over 9 years ago

0 Andy Liu (BMS) over 9 years ago

TI__Guru 52115 points

Hi Matsunami-san,

I will take a look at your question and try to give you some answer soon.

Andy

0 Andy Liu (BMS) over 9 years ago

TI__Guru 52115 points

Hi Matsunami-san,

Can I know why you would like to use this device as a mono audio amp?

Andy

0 Hidetoshi Matsunami over 9 years ago in reply to Andy Liu (BMS)

Expert 2750 points

Hello Andy,

It's my customer's demand.

I'm sorry I don't have any more information.

Best Regards,

Hidetoshi Matsunami

0 Andy Liu (BMS) over 9 years ago in reply to Hidetoshi Matsunami

TI__Guru 52115 points

Hi Matsunami-san,

My colleague sent me a reference circuit, which may satisfy your need.

Below is his comment:

"There is no Mono application in the datasheet but if we set external gain, and SE output configuration,

Like attached Truth Table and external resister connection, we can configure Mono mode.

SPK is connected between –Lout and -Rout. In this case both +Lout and +Rout side amplifiers are off.

Unfortunately we don’t have formal Mono application reference design ckt but attached configuration can do."

Attached is the reference circuit and the truth table.

Mono Configuration.pdf

Andy

0 Hidetoshi Matsunami over 9 years ago in reply to Andy Liu (BMS)

Expert 2750 points

Hello Andy,

I appreciate your support.

Please convey my thanks to your colleague.

Best Regards,

Hidetoshi Matsunami

0 Hidetoshi Matsunami over 9 years ago in reply to Andy Liu (BMS)

Expert 2750 points

Hello Andy,

I’d like to ask you (or your colleague) additional question.

Can the attached reference circuit connect to 1W speaker in SE mode?

There is the following information in the datasheet.

My customer has additional question.

Best Regards,

Hidetoshi Matsunami

0 Andy Liu (BMS) over 9 years ago in reply to Hidetoshi Matsunami

TI__Guru 52115 points

Hi Hidetoshi,

I think the question from your customer is like this: Could the output power of LM4838 achieve 1W for a 32 Ohm speaker if the the proposed SE mode reference circuit is used? Right?

Andy

0 Hidetoshi Matsunami over 9 years ago in reply to Andy Liu (BMS)

Expert 2750 points

Hello Andy,

I'm Sorry for not explaining enough.

Yes.

My customer thinks the output power of LM4838 can’t achieve 1W.

Best Regards,

Hidetoshi Matsunami

0 Andy Liu (BMS) over 9 years ago in reply to Hidetoshi Matsunami

TI__Guru 52115 points

Hi Hidetoshi-san,

Thank you for you explanation. I will try to offer you some answer soon.

Andy

0 Hidetoshi Matsunami over 9 years ago in reply to Andy Liu (BMS)

Expert 2750 points

Hello Andy,
I would like to know what the situation of this question is now.
Best Regards,
Hidetoshi Matsunami

0 Andy Liu (BMS) over 9 years ago in reply to Hidetoshi Matsunami

TI__Guru 52115 points

Hi Hidetoshi-san,

Sorry for my late response. I'm on my business travel in China now. I talked with colleague over you last question. The answer from us is yes. The LM4838 is able to output 1W into 8 Ohms load even with SE mode setting.

Andy

0 Hidetoshi Matsunami over 9 years ago in reply to Andy Liu (BMS)

Expert 2750 points

Hello Andy,
I appreciate your support.
I’ll tell it to my customer.
Best Regards,
Hidetoshi Matsunami