Interfacing a Low-voltage Processor with 3 V SD/SDIO or MMC Cards

摘要

Today's world of shrinking real estate, multiple power requirements, diverse interfaces and multiple solutions present the designer with a dizzying array of options. As processors evolve in complexity and function, they will place even more demands upon interface designs. Today, many digital baseband processors already have maximum I/O voltages restricted to as low as 1.8 V As processors advance and I/O and core voltages continue to drop, there is a growing discrepancy between the processor and peripheral I/O voltages.