针对现代系统芯片中处理器核等数字模块和模拟模块对于不同电平电源供电的需要,提出一种基于复用技术的新型双通路电荷泵实现方案.该电荷泵能同时提供具有驱动能力的升压和降压模式电压输出,且可实现可变增益组合,以便根据检测到的输入电压自动调整增益组合以提高工作效率.开关阵列和电容的复用降低了芯片和应用电路的成本.文章给出了电荷泵的拓扑结构和用于量化分析的大信号解析公式和小信号模型.电路在TSMC的0.35μm混合信号CMOS工艺下设计完成.仿真验证和流片测试的结果表明所提出的设计目标均已实现,所获结果与解析公式的计算高度一致,证明了模型以及分析方法的正确性.
To meet the demands for different supply voltage levels on SOC required by digital modules like CPU core and analog modules,a novel dual-output charge pump is proposed. The charge pump can output a step-up and a step-down voltage simultaneously with a high driving capability. The multiple gain pair technique was introduced to enhance its efficiency. The proposed co-use technology for capacitors and switch arrays reduced its cost. The charge pump was designed and fabricated in a TSMC 0.35μm mixed-signal CMOS process. A group of analytical equations were derived to model its static characteristics. A state-space model was derived to describe its small-signal dynamic behavior. Analytical predictions were verified by Spectre simulation and testing. The consistency of simulated results as well as test results with analytical predictions demonstrated the high precision of the derived analytical equations and the developed models.