Introduction

　　The Atmel ASIC Design Guidelines constitute a general set of recommendations intended for use by designers when preparing circuits for fabrication by Atmel. The guidelines are independent of any particular CAD tool or silicon process. They are applicable to Gate Arrays, Cell-Based ASICs (CBICs) and full-custom designs.

　　Although they do not give specific coding recommendations, they apply equally to designs captured in Verilog or VHDL as to designs captured as schematics.These guidelines do not cover general principles of ASIC design; rather they highlight specific design practices which are regarded as unsafe, and which can lead to devices which are difficult to test, and whose correct operation cannot be guaranteed under all circumstances. For each unsafe, and therefore non-recommended design practice, an alternative safe, and therefore recommended practice is proposed.