TPS54335A: TPS54335A Question, UVLO measurement different from the calculation result.

Bob Lee62837

Mastermind 7230 points

Part Number: TPS54335A

Dear support member,

My customer used TPS54335A.
I have a question about UVLO.

（Situation)
R1(VIN - ENpin)：430kΩ
R2(EN pin -GND)：33kΩ

Calculated of Datasheet
Vsart：17.3V
Vstop：13.5V

Measurement result
Vsart：17.3V
Vstop：12.5V

（Question）
When the input voltage is 12.5 V, the output voltage is turned off.
It is different from the calculation result. (Vstop: 13.5 V)
What is the cause?

Best regard.
Bob Lee.

over 6 years ago

0 Shawn Nie over 6 years ago

TI__Genius 10070 points

Hi,

If "R1(VIN - ENpin)：430kΩ; R2(EN pin -GND)：33kΩ", Vstart and Vstop should be 16.48V and 14.5V. Please double check the values of R1 and R2.

Shawn

0 Bob Lee62837 over 6 years ago in reply to Shawn Nie

Mastermind 7230 points

Dear Shawn Nie,

Thank you very much for your answer.

Since I want to sent schematic and waveform,
May I send it to your private email?

Best regard.
Bob Lee.

0 Shawn Nie over 6 years ago in reply to Bob Lee62837

TI__Genius 10070 points

Hi，

Sure, below is my email address.
shawn-nie@ti.com

Shawn

0 Bob Lee62837 over 6 years ago in reply to Shawn Nie

Mastermind 7230 points

Dear Shawn Nie,

Thank you very much for reply.

I sent to your private-Email address.
Could you check it?

Best regard.
Bob Lee.

0 Bob Lee62837 over 6 years ago in reply to Bob Lee62837

Mastermind 7230 points

Dear Shawn,

Thank you very much for support.
I solved.

Best regard.
Bob Lee.

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TPS54335A: TPS54335A Question, UVLO measurement different from the calculation result.