A 32-KB ePCM for Real-Time Data Processing in Automotive and Smart Power Applications

In the frame of power electronics applications, the request for smart and reconfigurable devices is pushing integration technologies in the direction of embedded systems. In this scenario, microcontrollers play a key role, and the availability of embedded non-volatile memory (eNVM) to store the microcontroller code has become crucial to enable real-time customization and increase system flexibility. Among emerging NVMs, phase change technology is becoming a very attractive solution for the development of applications for smart power and automotive markets. In this paper, a 32-KB embedded phase change memory (ePCM) designed and manufactured in 0.11- $\mu \text{m}$ smart power BCD technology with a specifically optimized Ge-rich Ge-Sb-Te (GST) alloy (supply voltage = 1.8 V) is presented. Thanks to the use of a differential sensing scheme, the proposed ePCM features 18-ns random access time with improved robustness against resistance drift. The word modify time under 32-cell programming parallelism was kept as low as 20 $\mu \text{s}$ , thanks to enhanced programming circuits. The size of the 32-KB eNVM is about 0.7 mm2.