TPS53515: switching frequency at output voltage is 5V

Jim Tsai

Expert 4470 points

Part Number: TPS53515

Hi,

My customer measure fsw is around 800kHz. VIn=12V, Vout=3.3V.

According to datasheet, it shows fsw spec typical value at output voltage is 3.3V.

Could you please provide fsw spec at output voltage is 5V?

over 2 years ago

0 Tomoya Ide over 2 years ago

TI__Expert 6271 points

Hi Jim,

The fsw selection and the spec provided are based on the resistor divider ratio as shown in Table 1, and it is independent of the output voltage.

Thank you,
Tomoya

0 Jim Tsai over 2 years ago in reply to Tomoya Ide

TI__Expert 4470 points

Hi Ide,

Sorry, let me clarify my question again.

My question is my customer's hardware design is 600kHz, but the test result is about 800kHz.

Due to the fsw spec in datasheet is base on Vout=3.3V.

My customer design is Vout=5V so we should expect the fsw will be higher than 600kHz, am I correct?

If so, what's fsw spec for Vout=5V when fsw hardware design is 600kHz? Or do you have any simulation/test result can provide to my customer for reference?

0 Miranda Gu over 2 years ago in reply to Jim Tsai

TI__Genius 14967 points

Hi Jim,

What's the resistor divider ratio (RDR) your customers are using?

0 Jim Tsai over 2 years ago in reply to Miranda Gu

TI__Expert 4470 points

Hi Gu,

Attached is customer's circuit. The divider is 249kohm on top and 107kohm on bottom

0 Miranda Gu over 2 years ago in reply to Jim Tsai

TI__Genius 14967 points

Hi Jim,

Have customers checked the actual resistance?

As Tomoya mentioned, the fsw selection provided are based on resistor divider ratio, which should be independent of output voltage.

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TPS53515: switching frequency at output voltage is 5V