What is a PWM chip. How is the processor powered on the motherboard

There are microcircuits and processors on the computer motherboard that require power of about 1V, etc. Such power does not come from the computer power supply and this voltage must be organized. For this, single-phase and multi-phase pulse power supplies are used, which are located on the motherboard

A single-phase power supply consists of one eight-pin PWM microcircuit with a control driver for the key, implemented on two field-effect transistors and an LC filter on a choke and a capacitor. Such a source powers a load that consumes an insignificant current, since with an increase in the consumed current, interference in the form of pulsations in the power supply increases

Such voltage with high power supply interference cannot be supplied to power the processor. The Intel Core 2DUO processor can consume current of 65 A and higher, and it also requires automatic power supply regulation from 0.85 to 1.5 V

To supply the processor with a large current and with the least interference on the power supply, multi-phase PWM microcircuits are used. These microcircuits can be two-, four-, six-phase, etc.

Such microcircuits have several outputs with a rectangular signal for controlling transistors. Each such output is a phase. If each phase made on transistor keys can conditionally supply a load with a current of up to 40A, then by adding two such phases together you can get one powerful output with a current of 80A at the output

Now all phases are combined and the output current is large, but what to do with the interference at the output, because they will also be combined and their amplitude will be large. To prevent the interference from combining, the PWM microcircuit sends a rectangular signal to the transistors shifted in time, as a result, the interference will also be phase-shifted at the output and will not have a large amplitude.

During the operation of the processor, it requires different supply voltage. To do this, the processor sends a signal to the multiphase PWM microcircuit, which in turn changes the duty cycle of the signal on the gates of the transistors, thereby increasing or decreasing the voltage for powering the processor.