Modern fabrication technologies facilitate the acceleration of processor throughput by enabling the integration of board-level functions, such as SERDES interface, memory interface and multiple types of processors, on a single chip. One of the direct results of fine transistor geometries is lower core power supply voltages, such as 1.2V. However, peripherals require their own power supply levels, depending on the communication interface type. As a result, multiple supply voltages are required to power these devices. Texas Instruments’ fixed and floating point DSPs, like the TMS320C6x family, also require multiple supply voltages.
Every microprocessor or DSP requires a reset generator circuit or IC to perform two functions: (1) start up from a fixed condition after the supplies are turned on, and (2) prevent the processor from executing instructions incorrectly and causing flash memory corruption when their power supplies are lower than the specified operating level. Traditional, simple, single-supply reset generators were adequate for single supply processors, but no longer are sufficient to guarantee reliable operation of multiple supply processors like the TMS320C6x. This white paper examines some of the challenges associated with resetting modern day processors.