PMIC용 저면적 64비트 MTP IP 설계

Abstract

본 논문에서는 저면적 64bit MTP IP를 설계하였다. 저면적 설계기술로는 MTP cell의 inhibit voltage를 기존의 VPP/3과 VNN/3 전압 대신 모두 0V를 사용하므로 VPPL(=VPP/3) regulator 회로와 VNNL(VNN/3) charge pump 회로를 제거하였다. 그리고 external pad를 이용하여 VPP program voltage를 forcing하므로 VPP charge pump 회로를 제거하였다. 또한 VNN charge pump는 VPP 전압을 이용하여 1-stage negative charge pump 회로로 pumping해서 -VPP의 전압을 공급하도록 설계를 하였다. 설계된 64bit MTP IP size는 <TEX>$377.585{\mu}m{\times}328.265{\mu}m$</TEX>(=0.124mm2)이며, DC-DC converter관련 layout size는 기존의 회로 대비 76.4%를 줄였다. In this paper, a 64b small-area MTP memory IP is designed. A VPPL (=VPP/3) regulator and a VNN (=VNN/3) charge pump are removed since the inhibit voltages of an MTP memory cell are all 0V instead of the conventional voltages of VPP/3 and VNN/3. Also, a VPP charge pump is removed since the VPP program voltage is supplied from an external pad. Furthermore, a VNN charge pump is designed to provide its voltage of -VPP as a one-stage negative charge pump using the VPP voltage. The layout size of the designed 64b MTP memory IP with MagnaChip's <TEX>$0.18{\mu}m$</TEX> BCD process is <TEX>$377.585{\mu}m{\times}328.265{\mu}m$</TEX> (=0.124mm2). Its DC-DC converter related layout size is 76.4 percent smaller than its conventional counterpart.