LM5176-Q1: I have some questions about the design of the LM5176-q1 IC.

Jongmin Lee

Prodigy 30 points

Part Number: LM5176-Q1

We are applying LM5176-q1 to our product.

Q1:

I am using 1% tolerance of the feedback resistance connected to the FB pin of the lm5176-q1 product.

Is there any problem using 1%??

Q2:

What is the control method of lm5176-q1? PI control, etc.

Q3:

I am using R5%, C5%, R1% for the comp pin circuit. Any problems with Toelrance?

over 2 years ago

+1 Feng Ji over 2 years ago

TI__Mastermind 22650 points

Hi Jongmin,

Q1: 1% tolerance resistor is most common used feedback resistors for good accuracy.

Q2: The PWM control scheme is based on valley current mode control for buck operation and peak current mode control for boost operation.

Q3: Generally this tolerance is good enough. You may use LM5176 Design Calculator to check the influence to your control loop.

Best Regards,

Feng Ji

+1 Jongmin Lee over 2 years ago in reply to Feng Ji

Prodigy 30 points

Thank you for answer.

I have additional questions.

Q : Is there a function or mechanism to protect the FET in the IC in case of Hi-side and Low-side short of the FET module composed of H-Bridge? (Except for Over Current Detection)

+1 Feng Ji over 2 years ago in reply to Jongmin Lee

TI__Mastermind 22650 points

Hi Jongmin,

45ns dead time is added between the high side driver and low side diver to avoid shoot through.

Best Regards,

Feng Ji

+1 Jongmin Lee over 2 years ago in reply to Feng Ji

Prodigy 30 points

Right. I already know there is dead time.

However, if a shoot through situation occurs, is there any mechanism other than Overcurrent Detection to protect the FET Module?

Thank you for quick response.

+1 Feng Ji over 2 years ago in reply to Jongmin Lee

TI__Mastermind 22650 points

Hi Jongmin,

The controller cannot detect shoot through.

Best Regards,

Feng Ji

Power management

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LM5176-Q1: I have some questions about the design of the LM5176-q1 IC.