A 24-MB Embedded Flash System Based on 28-nm SG-MONOS Featuring 240-MHz Read Operations and Robust Over-the-Air Software Update for Automotive Applications

Abstract

This letter presents an embedded flash (eFlash) system based on 28-nm split-gate MONOS (SG-MONOS) with high- ${k}$ metal gate CMOS process technology for automotive applications. It contains the world’s largest 24-MB memory capacity (4-MB code flash macro (CF) $\times6$ ) and achieves 240-MHz random read access at Tj from −40 °C to 170 °C, and read throughput reaches 46 GB/s by reading 6 CFs in parallel. The peak current consumption during over-the-air software update (OTA) is reduced by 55% in low-noise program mode. A high-speed program mode for factory program and test achieves 6.5-MB/s program throughput by programming 2 CFs in parallel. In OTA, the eFlash system realizes ~1 ms software switching and robustness against unintentional OTA termination.