Issue link: https://resources.mouser.com/i/1442868
30 these chips' power requirements. Putting more of those high density components onto a printed circuit board (PCB) makes power delivery even more challenging. As voltage drops and operating voltage ranges grow narrower, devices become more susceptible to noise. As a result, designs require placing capacitors as close to the load as possible, but there are limitations based on the number and size of capacitors needed to deliver the power required. The smallest capacitor size is 01005 inches, which can fit between the pins of a small chip. Anything smaller than that becomes part of the packaging technology. Some chip providers integrate capacitors into the chip packages so that it's not necessary to put as many of them on the PCB. Another approach that eliminates the need to place capacitors on the board is to have the power supply sit directly on top of the chip, which allows for denser designs and reduces the impact of system noise. The downside is that these components have a height requirement, and you have to dissipate heat through some kind of heat sink. If you can make this design work physically, it simplifies PDN design on the board because it places the power supply right next to the load. PCB fabrication techniques can help you create more compact designs without actually using smaller components. For instance, there are limits on how small discrete capacitors can be. If you need more capacitance in a dense design, another approach is to use the capacitance between multiple layers of the PCB itself. Simulation is an essential tool for balancing these approaches to power distribution, but with simulation, you can never simulate your entire design in one go. It's just too computationally expensive, and the simulation tools are running on a lot of assumptions. In fact, the most accurate aspect of the simulation is the geometry of the PCB because that is coming directly from the computer-aided design tool. All the models vendors provide for capacitors or integrated circuits or other components have assumptions built into them. It's important to run A-B simulation comparisons, but ultimately you must make real-world measurements of things you cannot do in simulation. '' Some chip providers integrate capacitors into the chip packages so that it's not necessary to put as many of them on the PCB."