TPS563257: Switching frequecy

Jeff YANG

Part Number: TPS563257

Tool/software:

Hi,

As shown in the figure below, under the following conditions the TPS563257’s estimated maximum switching frequency is around 900 kHz.

So will the TPS563257 automatically reduce its operating frequency from 1.4 MHz to about 900 kHz?

Or it not impact by Vin/Vout ratio, always keep Switching frequecy ~1.4Mhz?

Thanks!

0 Alla Ushasri 6 days ago

Hi Yang,

Min duty cycle that TPS563257 can go is 7.2% but with the current specs the duty cycle is 5.41% so try reducing Vin to achieve 0.65V Vout.

Best regards,

Usha.

0 Jeff YANG 6 days ago in reply to Alla Ushasri

Hi Usha,

You mean TPS563257 can't design in 12V to 0.65V condtion?

I use webebch seems it work. So I need low down Vin to 0.65V/7.2%= 9.02V?

Thanks!

Jeff

0 Alla Ushasri 5 days ago in reply to Jeff YANG

Hi Jeff,

It is at corner, so if you try to reduce Vin switching losses will also decrease i.e efficiency will increase.

So, recommended Vin is 6V.

Best regards,

Usha.

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