TPS61236P: TPS61236P question. there is a problem that this IC sounds an abnormal noise during operation.

Bob Lee62837

Mastermind 7230 points

Part Number: TPS61236P

Dear support member,

My customer used TPS61236P.
This project is urgent.

(Situation)
Regulator TPS61236PRWLR, but we are currently implementing it in our prototype and checking its operation.

Voltage etc. are output correctly, there is no problem as a circuit.

It is a problem that this regulator IC sounds an abnormal noise during operation.

I also tried this reference board（TPS61236EVM), but I heard a noise similarly.

（Question）
1. Does this regulator IC sound such an abnormal sound?
2. How can I stop or mitigate this noise?
3. What is the cause of this abnormal noise?

Best regard.
Bob Lee.

over 5 years ago

0 Jasper Li over 5 years ago

TI__Mastermind 46905 points

Hi Bob,
the audible is normally caused by the ceramic capacitor. the ceramic capacitor will vibrate if there is voltage ripple. the vibration could causes audible noise if the voltage ripple frequency at the output ceramic capacitor is within the audible frequency range.
the inductor may also generate similar sound because of the current.

could you measure the voltage ripple at the input and output capacitor to double check its frequency?

0 Bob Lee62837 over 5 years ago in reply to Jasper Li

Mastermind 7230 points

Dear Jasper Li

Thank you very much for quick reply.

I confirm about ripple frequency.

Best regard.
Bob Lee.

0 Bob Lee62837 over 5 years ago in reply to Bob Lee62837

Mastermind 7230 points

Dear Jasper Li

Thank you very much for reply.

Since I want to send waveform,
Could you teach your private address?

Best regard.
Bob Lee.

0 Jasper Li over 5 years ago in reply to Bob Lee62837

TI__Mastermind 46905 points

Hi Bob,
you can attach the waveform to the post.
or add me as friend and send the waveform to me.

0 Jasper Li over 5 years ago in reply to Jasper Li

TI__Mastermind 46905 points

Hi Bob,
I haven’t heard back from you, I’m assuming you were able to resolve your issue. If not, just post a reply below

0 Bob Lee62837 over 5 years ago in reply to Jasper Li

Mastermind 7230 points

Dear Jasper Li,

I'm sorry late for reply.

My customer used at output current 0.015A specification.
TPS61236P was operating in PFM, switching at 6 kHz frequency.
There was a sound at this 6 kHz.
Although it was able to reduce by adding an electrolytic capacitor, it is difficult due to the application size.

May I ask a question?
Is there a way to operate this TPS61236P with fixed PWM?

Best regard.
Bob Lee.

0 Jasper Li over 5 years ago in reply to Bob Lee62837

TI__Mastermind 46905 points

Hi Bob,
other solution is to reduced the caramic capacitor and add tantalum capacitor. there is no measure to force the device into fixed PWM. the operating mode is only defined by the output current.

Because of the Thanksgiving holiday in the U.S., TI E2E™ design support forum responses may be delayed from November 25 through December 2. Thank you for your patience.

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TPS61236P: TPS61236P question. there is a problem that this IC sounds an abnormal noise during operation.