ULS

Abstract

Power dissipation is a major bottleneck for emerging applications, such as implantable systems, digital cameras, and multimedia processors. Each of these applications is essentially designed as an Analog/Mixed-Signal System-on-a-Chip (AMS-SoC). These AMS-SoCs are typically operated from a single power-supply source which is a battery providing a constant supply voltage. In order to reduce power dissipation of the AMS-SoCs, multiple-supply voltage and/or variable-supply voltage is used as an attractive low-power design approach. In the multiple-/variable-supply voltage AMS-SoCs the use of a DC-to-DC voltage-level shifter is critical. The voltage-level shifter is an overhead when its own power dissipation is high. In this article a new DC-to-DC voltage-level shifter is introduced that performs level-up shifting, level-down shifting, and blocking of voltages and is called Universal Level Shifter (ULS). The ULS is a unique component that reduces dynamic power and leakage of the AMS-SoCs while facilitating their reconfigurability. The system-level architectures for three AMS-SoCs, such as Drug Delivery Nano-Electro-Mechanical-System (DDNEMS), Secure Digital Camera (SDC), and Net-centric Multimedia Processor (NMP) are introduced to demonstrate the use the ULS for system-level power management. The article presents a design flow and an algorithm for optimal design of the ULS using a dual- V th high-κ technique for efficient realization of ULS. A prototype ULS is presented for 32nm nano-CMOS technology node. The robustness of the ULS design is examined by performing three types of analysis, such as parametric, load, and power. It is observed that the ULS produces a stable output for voltages as low as 0.35 V and loads varying from 50 fF to 120 fF . The average power dissipation of the ULS with a 82 fF capacitive load is 5 μ W .