Components of Central Processing Unit (CPU)
A CPU has following components:
1. Datapaths (such as ALUs and pipelines)
2. Control unit: logic which controls the datapaths
3. Memory components such as register files, caches
4. Clock circuitry such as clock drivers, PLLs, clock distribution networks
5. Pad transceiver circuitry
6. Logic gate cell library which is used to implement the logic

Phase-locked Loop(PLL)
A phase-locked loop or phase lock loop (PLL) is a control system that generates a signal that has a fixed relation to the phase of a "reference" signal. A phase-locked loop circuit responds to both the frequency and the phase of the input signals, automatically raising or lowering the frequency of a controlled oscillator until it is matched to the reference in both frequency and phase. A phase-locked loop is an example of a control system using negative feedback.

Pad transceiver circuitry
A transceiver circuit for an integrated circuit having a pad located therein, a receiving circuit connected to the pad for receiving digital data signals therefrom, a transmitting circuit connected to the pad for transmitting digital data signals to the pad, characterized by output resistance control means connected to said transmitting circuit and arranged to dynamically retain said output resistance of the transmitting circuit at a constant value during data signal transmission from said transmitting circuit.

Logic gate cell library
A standard cell library is a collection of low level logic functions such as AND, OR, INVERT, flip-flops, latches and buffers. These cells are realized as fixed height, variable width full custom cells. The key aspect with these libraries is that they are of a fixed height, which enables them to be placed in rows, easing the process of automated digital layout.