Class D Amplifier as Power Inverter?

johny radio

Intellectual 900 points

Other Parts Discussed in Thread: TAS5612LA, TPA3255, TPA3223

Can the TAS5612LADDVR or another chip be used as a power supply?

I need a unipolar sinusoidal AC constant-voltage power source

100 kHz sine out
0V to 5V RMS
0A to 25A continuous
125W continuous
Inductive load
input: 12V to 24V DC

So, the "audio" input would be a 100 kHz sine wave.

I assume to regulate output voltage, i would change the amplitude of the input sine.

over 2 years ago

0 Damian Lewis over 2 years ago

TI__Mastermind 34775 points

Hello Johny,

No, the input requires a PWM signal, not a sine wave.

0 johny radio over 2 years ago in reply to Damian Lewis

Intellectual 900 points

A class D audio amplifier has an audio input.

That audio is compared to a high-frequency triangle wave to generate high-frequency PWM.

In my proposal, the audio input would be a sine wave.

0 Luis Fernandes de Pina over 2 years ago in reply to johny radio

TI__Genius 15080 points

Hello Johny,

The TAS5612LA is a Power Stage so the input is a PWM controller not an audio input, you can look at something like a TPA3255 but we do not validate the behavior of the device for ultrasonic signals esp as high as 100kHz so cannot guarantee performance or functionality for your use case. However you are welcome to use an EVM to test this behavior to see if it fits your use case.
best regards,
Luis

0 johny radio over 2 years ago in reply to Luis Fernandes de Pina

Intellectual 900 points

I see, thank you.

Nevermind the TPA3255.

Which device do you recommend for my application? The TAS5612LA ?

I seek a device validated for 100 Khz at 100W.

Thanks!

0 johny radio over 2 years ago in reply to Damian Lewis

Intellectual 900 points

I understand now, thank you.

Assuming i provide the PWM input, do you recommend the TAS5612LADDVR for 100 kHz at 100W?

Or some other device?

Thx!

0 Shadow He over 2 years ago in reply to johny radio

TI__Mastermind 48780 points

Hi Johny

johny radio said:
Assuming i provide the PWM input, do you recommend the TAS5612LADDVR for 100 kHz at 100W?

You could have a try with it. As the inner control loop bandwidth for high power devices is only 80KHz to 100KHz, your using should already beyond the bandwidth. Meaning the amplitude of the signal will be decreased, you can't expected to have correct Gain as this device original designed. We don't have data about this using, but you could still have a try.

johny radio said:
Or some other device?

You could also consider try with TPA3223, which is analog input and this device is newer, but the problem is the same. You still need to try with it.

Sorry that we don't have device family that is specially designed for ultra-sound using.

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Class D Amplifier as Power Inverter?