TPS60400: is there any equations for getting know how much C fly are needed?

Masaharu Takahashi

Part Number: TPS60400

Hi, All.

could you tell me below?

・is there any equations for getting know how much C fly are needed?

* I know its datasheet shows its recommended value though, Customer needs to explain why they use the value of C internally.

please answer for it.

・Do we have the graph which shows the relationship between temp and Vout to see how much output voltage varies across the temp range datasheet specifies?

over 5 years ago

0 Tanvee over 5 years ago

TI__Genius 17301 points

Hi Takahashi-san,

There is no straightforward equation for calculation. The value defined in the datasheet is validated in the lab and suitable for most of the applications. Figure 1 shows the relationship between output current and temp with different input voltage help to calculate the output voltage.

Best regards,

Tanvee

0 Masaharu Takahashi over 5 years ago in reply to Tanvee

TI__Expert 4170 points

Hi, Tranvee-san

Could you tell me with more steps?

Fig1 shows the relationship between efficiency vs output current.

what customer wants to know is the relationship between temp and Vout.

how we could utilize fig1 to know what customer wants to know.

could you teach me here otherwise customer won't get the point as well.

0 Tanvee over 5 years ago in reply to Masaharu Takahashi

TI__Genius 17301 points

Hi Takahashi-san,

Figure 1 will just help to find the output voltage in different conditions at room temp. Unfortunately, the data for output voltage at different temp is not characterized.

Best regards,

Tanvee

0 Masaharu Takahashi over 5 years ago in reply to Tanvee

TI__Expert 4170 points

Do you think that temp affects on how accurate output voltage IC does ?

0 Tanvee over 5 years ago in reply to Masaharu Takahashi

TI__Genius 17301 points

Hi Takahashi-san,

The difference in temperature will affect Rds of the device and change the output voltage for sure but the changes in output voltage are not drastic.

Could you provide more information about the application to understand the concern?

Best regards,

Tanvee

0 Tanvee over 5 years ago in reply to Tanvee

TI__Genius 17301 points

Hi,

Is the issue is solved? If yes I am closing the thread. Please open a new thread for further discussion.

Best regards,

Tanvee

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TPS60400: is there any equations for getting know how much C fly are needed?