A 2.4 pJ ferroelectric-based non-volatile flip-flop with 10-year data retention capability

Abstract

A ferroelectric-based (FE-based) non-volatile flipflop (NVFF) is proposed for low-power LSI. Since leakage current in a logic circuit can be cut off by non-volatile storage capability of NVFFs, the standby power is reduced to zero. The use of complementarily stored data in coupled FE capacitors makes it possible to achieve 88% reduction of FE capacitor size while maintaining a wide read voltage margin of 240mV (minimum) at 1.5V, which results in 2.4pJ low access energy with 10-year, 85°C data retention capability. An access speed of FE capacitors can be adaptively changed according to required retention time, which becomes 1.6fLs for 10-year data retention, and 170ns for 10-hour data retention. Especially, short-term data retention is suitable for power gating implementation. Applying the proposed circuitry in 32bit CPU of a vital sensor LSI, its power consumption becomes 13% of that of conventional one with area overhead of 64% using 130nm CMOS with Pb(Zr,Ti)03(PZT) thin films.

Dual Mode Ferroelectric Transistor based Non-Volatile Flip-Flops for Intermittently-Powered Systems

“…5(a)). This is unlike previous designs [5][6][7][8] where the NV element is in a separate B/R module, interfacing the FF via external control signals. (Note, embedding of FEFET in FF is challenging because of the requirement of VGS<0 for P switching).…”

“…Also, high write current during backup increases their power consumption [7]. Ferroelectric (FE) capacitor based designs have also been proposed, utilizing their property of polarization (P) retention in the absence of electric field (E) [8]. However, low distinguishability between their non-volatile states degrades the robustness during restore operation.…”

Recent Progress of Biomedical Processor SoC for Wearable Healthcare Application: A Review

“…To realize both nonvolatility and high-speed access characteristics, a 6T-4C memory cell coupling an SRAM cell and ferroelectric capacitor was developed. Furthermore, nonvolatile technology was introduced into all the Flipflops embedded in Nonvolatile MCU [72], [73] as shown in Fig. 15.…”

Enabling Internet-of-Things with Opportunities Brought by Emerging Devices, Circuits and Architectures

“…As both logic and memory are intrinsically nonvolatile, there is no need for backup and restore controls for the NCFET storage. The baseline design uses conventional CMOS transistors for logic, a clustered FeRAM array as data and instruction memory, and NV-DFF using ferroelectric capacitor for state backup under external control [58]. Giving the harvested RF power from TV stations, as shown in the power profile sampled per 0.2S in Fig.…”