TPS652510: Power supply to Artix-7 XC7A35T-2FT256

Hi, Stuart 

Some comments: 

1. Why do you select TPS652510? there are some newer parts: TPS65261, TPS65263, recommend to choose the new devices. 

2. Yes, there is no Webench to calculate the TPS652510's efficiency. 

But for the TPS65261, TPS65263 devices, I can check the efficiency data for you, what is the max loading of every channel? Maybe you can check the efficiency curve in datasheet. 

Besides, not recommend setting Fsw to 1.5MHz which will cause more switching loss. 

you can refer the EVM reference design, set Fsw to 600kHz. 

https://www.ti.com/lit/ug/slvua85a/slvua85a.pdf?ts=1628067206336&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTPS65261%253FkeyMatch%253DTPS65261%2526tisearch%253Dsearch-everything%2526usecase%253DGPN 

https://www.ti.com/lit/ug/slvua83a/slvua83a.pdf?ts=1628067243270&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTPS65263%253FkeyMatch%253DTPS65263%2526tisearch%253Dsearch-everything%2526usecase%253DGPN 

Hi Zhao Ma,

1. TPS65261 is good candidate but it was out of stock in digikey

Also I just want to set voltage by hardware and don't waste resource to control via I2C, I will consider to TPS65263

2. 

 - 1V / 2A channel is about 1 - 1.5A

- 1.8V/ 2A channel is about 0.5 - 1A

- 3.3V /3A channel is about 2A

Thanks for your feedback.

Stuart.

1. Okay. 

2. See the efficiency as below assume Vin=12V, Fsw is set to 600kHz. 

- 1V / 2A channel is about 1 - 1.5A  --> Eff is about 75%@1.5A  

- 1.8V/ 2A channel is about 0.5 - 1A  --> Eff is about 85.2%@1A 

- 3.3V /3A channel is about 2A  --> Eff is about 90.4%@2A   

Hi Zhao,

It's great, thank you so much.

One more question, How about is accuracy output voltage on channel 1V / 2A? 

Because, Requirement of voltage rail 1V is 3% . 

I know the answer will depend on our real design but if you have any experience before, please let me know.

Thanks.

Hi, Stuart 

The output accuracy is related with the reference of IC and FB divider resistor tolerance. 

From the datasheet, the VREF is +/-2% over -40C to 125C. 

So Suggest selecting 1% resistor, then you can achieve +/-3 accuracy.