Asic

In short pre-silicon refers to before fabrication..pre-silicon tetsting is done to make sure your design functions as promised and as in specs. post-silicon testing is similary testing after it is fabricated. you make sure the wafer/chip is working properly functionality/timing wise.

In presilicon validation, emulation and simulation are used to shake out defects. The simulation environment can be broken into two major pieces: system-level simulation and full-chip simulation. The latter is concerned with testing clusters on the silicon from the pins inward; the former uses an environment where the code representing the silicon is in a platform environment. Bus-functional models of the various interfaces representing the target platform are connected together to run various combinations of random and focused tests to test data flow as well as bus protocols. An example is having several PCI bus masters simultaneously driving and receiving data into the platform. Emulation is used by synthesizing the silicon register-transfer-level (RTL) model into FPGAs and running the chip set functionality on a real target platform as a gate to tapeout. The technologies used in post-silicon to verify functionality are system validation (SV), analog validation (AV) and compatibility validation (CV). SV represents controlled, synthetic cycles at every interface in a platform environment. AV verifies signal integrity, and CV runs in a real-life operating system with off-the-shelf peripherals and applications.