Class AB Amplifier for BTL

Anand Sethi

Other Parts Discussed in Thread: LM4950, TPA3111D1

I have a requirement for driving 4W into a 4 ohm speaker load. I want this as a BTL configuration. I was planning on using LM4950 but it does mention that I can only use 8 ohm in BTL configuration. What is the reason for that and is there any other amplifier that TI can recommend. Thanks.

over 9 years ago

0 Don Dapkus over 9 years ago

TI__Guru**** 189399 points

Hi, Anand,

BTL into a 4-ohm load presents a pretty tough load for a class-AB amplifier. I think you will need to go for a much larger amplifier in order to achieve your goal.

We have many class-D amps that can do this, for example, TPA3111D1.

-d2

0 Anand Sethi over 9 years ago in reply to Don Dapkus

Prodigy 115 points

Class D is not possible because of EMI. Why cant BTL drive into 4 ohm load? Which graph shows that it is not possible? I do know the curves are not characterized below 5 ohms. Thanks!

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Class AB Amplifier for BTL