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Class D Audio Amplifier IC Forum Discussions

TrueTed
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Hi,

  We're at the point of deliberating the floating power supply (VAA and VSS) design. We'd like to pull up the power pin with an external resistor and capitalize on the internal Zener diode for regulatiing.

Then we find something we couldn't realize that the supplying current the these pins are both around 14.5mA and 1~1.7mA at idle and off status. But the datasheet shows them in 5~7.5mA and 1.5~3mA. I can't realize where the differences between 14.5mA of evaluation board and 7.5mA of specifications. We didn't find similar differences in IRS2092 before.

Thanks for your help,

Ted

 

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Sodum
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Hello @TrueTed ,

"Floating Input positive quiescent supply current" is a static DC value without PWM switching.

The supply current to the OTA increases when PWM frequency is higher in operating conditions.

CSD pin affects the IQAA. The highest is when CSD is in the middle between VAA and VSS during startup mode.

Please refer the below image from datasheet,

Sodum_0-1657282324695.jpeg

Regards,

Premsagar S

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Sodum
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Hello,

Thank You for posting your query in the Infineon community.

The supply current mentioned in the datasheet (page no. 11) "Floating Input positive quiescent supply current" is 7.5mA. This is  quiescent current (No load) current. Can you please let us know what is the load status during your validation.

Sodum_0-1656772938132.png

Regards,

Premsagar S

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TrueTed
Level 1
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Level 1

Are you sure the current is load dependent? I've investigated IRS2092's VAA and VSS working current were really matching it's "quiescent" current. And what made the current different was the control pin (CSD) status. I think oscillation frequency does matter as well.

I measured the VAA and VSS current on an IRAUDAMP25 evaluation board and the working current was just around 15mA regardless the speaker load.

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Sodum
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Hello @TrueTed ,

"Floating Input positive quiescent supply current" is a static DC value without PWM switching.

Can you please let us know, which evaluation board are you using for testing (EVAL_MA5332 or REF_MA5332).

Regards,

Premsagar S

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TrueTed
Level 1
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Hi Premsagar,

The evaluation board which I have is EVAL_AUDAMP25.

Thanks and Best Regards,

Ted

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Sodum
Moderator
Moderator 50 sign-ins 10 solutions authored 5 solutions authored
Moderator

Hello @TrueTed ,

"Floating Input positive quiescent supply current" is a static DC value without PWM switching.

The supply current to the OTA increases when PWM frequency is higher in operating conditions.

CSD pin affects the IQAA. The highest is when CSD is in the middle between VAA and VSS during startup mode.

Please refer the below image from datasheet,

Sodum_0-1657282324695.jpeg

Regards,

Premsagar S

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