Power supply for FPGA

[luudee]

I recommend you look at the product page of the controller chip MAX15301:
https://www.analog.com/en/products/max15301.html

And also try to find some generic information how DC/DC Buck converters work: do a Google search for "Operational Theory of DC/DC Buck converters"

Try to understand the underlying theory first, before jumping in to an advanced schematic. It is impossible to explain that in a couple of posts in a forum .


Good Luck !
luudee

[joniengr081]

Hi, I have now studied how DC-DC buck converters works and I also have read the datasheet of MAX15301 again and found that the output voltage is set by a resister Rset at pin number 3. There 1 describe the resistor values and the output voltages.

I also found that there is a SYNC pin number 1 at which switching frequency resistor has to be connected. In the section Setting Switching Frequency they have mentioned that "As a guideline, lower frequencies can be used to improve efficiency, while higher frequencies can be selected to reduce the physical size and value of the external filter inductor and capacitors." Is this true only for this chip or is true in general for switch mode DC-DC converters ?

In the schematic of Xilinx KCU 105, they have used four FETs instead of two which is mentioned in the datasheet of MAX15301. I guess they did this to optimize the power supply for current up to 40 A then another question comes in my mind that how to test the power supply card ? I know that there exist a programmer "Maxim PowerTool MAXPOWERTOOL002# USB-to-PMBus" which can be bought separately to configure and monitor the chip MAX15301 through I2C in the power supply card but what about the load ? What kind of load can be connected at the output to test the power supply card for 1 V  power supply delivering 40 A current ? which is like 40 Watt rating resistor

[luudee]

> "As a guideline, lower frequencies can be used to improve efficiency, while higher frequencies can be selected
>  to reduce the physical size and value of the external filter inductor and capacitors." Is this true only for this chip
>  or is true in general for switch mode DC-DC converters ?

This is typically true for all DC/DC Buck converters.



> What kind of load can be connected at the output to test the power supply card for 1 V  power supply delivering
> 40 A current ? which is like 40 Watt rating resistor


Typically, people who design any type of power supply, use a "Electronic DC Load" for testing purposes.

For example, I use   IT8513C+   made by ITECH ...

But you can also use a resistor. You can use plain copper wire to make a simple resistor for Power Supply testing.



Have Fun !

luudee