Abstract: The requirement of IoT sensor node SoC is strict. In most application scenario, there is no need that all the modules keep working all the time. Only a few modules need to work instead. We propose the idea of power management, realizing multi-work mode with clock management and power management, as well as using the least number of modules to work. Power management is able to support work mode, sleep mode and deep-sleep mode, the current is only 0.47 μA at the voltage of 1.08 V and the frequency of 32 kHz, fabricated with SMIC 130 nm.