LM4674: 300ohm resistor at the output terminal

Roy Hsu

Genius 9320 points

Part Number: LM4674

Hi Team,

What's the purpose of the 300ohm resistor at the output terminals?

Thanks!

Roy

over 3 years ago

0 Luis Fernando Rodriguez S. over 3 years ago

TI__Guru* 84915 points

Hi, Roy,

The 300ohms resistor acts like a load in case there's no speaker connected. In case the speaker load is connected, this resistor will be negligible since the speaker load would be in ~8ohms range.

Please let me know if you have further questions or comments.

Best regards,
Luis Fernando Rodríguez S.

0 Roy Hsu over 3 years ago in reply to Luis Fernando Rodriguez S.

TI__Genius 9320 points

Hi Luis Fernando,

But why is this dummy load needed at the first place? Can I remove it even when no speaker is connected?

Thanks!

Roy

0 Luis Fernando Rodriguez S. over 3 years ago in reply to Roy Hsu

TI__Guru* 84915 points

Hi, Roy,

Yes, this dummy load can be removed when no speaker is connected. This was placed in the EVM just for evaluation purposes.

Best regards,
Luis Fernando Rodríguez S.

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LM4674: 300ohm resistor at the output terminal