With the global energy transition and the promotion of the "dual carbon" strategy，the optimization of electric vehicle charging technology has become one of the core issues in the development of the new energy vehicle industry. This paper proposes a hardware control architecture based on a voltage divider circuit，multi-stage comparator，and RS flip-flop to address the high complexity and high cost of traditional charging systems that rely on microcontrollers and power management chips. The aim is to achieve energy balance and stability during the charging process. Through the dynamic threshold adjustment mechanism and fault-tolerant design of bistable triggers，the system can complete multilevel voltage detection and charging mode switching without software dependency，reducing hardware costs by more than 50%. Experimental verification shows that the design meets the design requirements in terms of voltage division accuracy（±1%），comparator response time（<1ms），and anti-interference ability，providing technical support for the popularization and safety improvement of charging infrastructure.