TPS54519: Design Tool for Output Voltage Adjustment Using a DAC

Hi Michael,

The external components selection depends on the operating condition of the device. I would suggest using Webench to get the accurate components value for your application.

However, both devices cover different features. Can you help to understand why you want to switch from TPS62088 to TPS54519 ? It can help me to suggest you other devices that can better fit your application.

Best Regards, Tanvee

Hi Tanvee,

Here is for your information and my request.

They didn't use TPS62088 and reviewed application file only for PWM control.

They need 5A output and so they are using this part for CPU Core power.

Pls refer to their condition is as below.

Vin :5V

Vout : typ. 0.95V (Range 0.87V~0.99V)

PWM : 120KHz

In the above condition, could you please give me R3,Cfiter,Rfiter value?

Best regards,

Michael

Hi Michael,

I am attaching the link that can support you in giving the external comp setting values. 

 https://webench.ti.com/power-designer/switching-regulator/customize/636?VinMin=5&VinMax=5&O1V=0.95&O1I=5&base_pn=TPS54519&AppType=None&Flavor=NA&op_TA=30&origin=pf_panel&lang_chosen=en-US&optfactor=3&Topology=Buck&flavor=NA&VoltageOption=NA

I would also suggest looking at our new devices like TPS62816-Q1 and TPS6287x-Q1 which can support the above conditions and with a higher switching frequency with lower inductor values.

Let us know if you need further help here.

Best regards,

Tanvee

Hi Tanvee,

Thanks for your kind support.

Your link has happened error as below.

Could you please check again and give me feedback?

Best regards,

Michael

Hi Michael,

You can get the WEBENCH model on this product folder link: https://www.ti.com/product/TPS54519

. I would highly recommend using the model to generate the model for your operating condition with different external components selection. 

Best regards, Tanvee

Hi Tanvee,

I can also use WEBENCH for this part.

Finally, Our customer want to add external circuit R3, Cfiter, Rfiter to TPS54519 as below reference circuit of TPS62088.

Typ. output voltage is 0.95V and want to adjustable from 0.87V to 0.99V through external circuit with PWM.

Their system condition is

Vin :5V

Vout : typ. 0.95V (Range 0.87V~0.99V)

PWM : 120KHz

I want to get R3, Cfiter, Rfiter value.

Best regards,

Michael

Hi Michael,

I would suggest using the Webench model available on the link shared before.

It can help you to choose the external components according to your requirements.

Thanks, Tanvee

Hi Tanvee,

I totally don't understand what you mean.

Because the WEBENCH of TPS54519 does not have the external components R3, Cfiter, Rfiter that I requested.

Below is what I sent it to you for your reference.

Can't you give me what I requested?

If you can, please provide a value that meets the customer's condition.

Best regards,

Michael

Hi Michael,

First, you have to understand the device's operation. The Schematic shared here and TPS54519 are completely different which made confusion.

If you want to operate the device with an additional feedback divider you have to take care of the feedback voltage on the pin only.

Both devices have the same reference voltage which means you can use similar values for R3, C filter, and R filter. The main thing has to take care of the threshold of voltage which should not be higher than 0.6V.

Regard,

Tanvee

Hi Tanvee,

Thanks for your feedback.

Could you explain to me what's the means about "threshold of voltage" at your comment?

Do you mean the voltage between C1 and R3? right?

Your comment is that "The main thing has to take care of the threshold of voltage which should not be higher than 0.6V."

Best regards,

Michael