What is a point-of-load converter?

Hello Hari, Thank you for posting.

I will provide an example of a PoL, Point of Load application.

A typical PC desktop system will have a power supply inside the chassis in it's own metal box.
A multi wire cable connects from the Box supply down to the motherboard.
The cable will have 5V, 12V, maybe 3.3V, and possibly some negative rails., powergood-reset, grounds, etc.

The Processor on the motherboard needs very low voltages at high currents.
1V with 100Amp transient spikes is very common.
The 100Amps can not be sent down the cable from the Box supply because of high resistive losses.
And the 1V could not be maintained within the tight tolerance required because of the resistive and inductive cable losses.
Even with remote sense, the regulation at processor could not be kept within specification.

Therefore, a switching converter would be located on the motherboard directly next to the processor.
The processor is the load, and this converter is located "at the Point of Load"
This converter would use +12V as its input, create 1V at 100Amps using multiple phases, for the processor core.
12V current (assuming 100% efficiency) would be 8.3Amps in order to provide 100Amps at 1V, 100W.

PoL supplies are located directly where they are needed.
They provide tight DC regulation and excellent transient response.

Is this the explanation you were looking for?

Hi Walker,

Thank you very much.

My understanding is first we need to use an IC which provide different ouput rails like 3.3V,12V etc and we need to connect the output of this IC to the I/P of Switcher or LDO placed near to the load.Please correct me if I am wrong.
Can I use any switcher or LDO or there are specific IC's forPOL application.

Regards
hari