建立了梯度法的开关电容电路结构，分析了最速下降法、牛顿方法和拟牛顿法的共同特点，研究无约束差分优化的开关电容电路结构。通过计算机仿真实例，证明了该电路收敛速度较快，且随着有关参数的改变，可在不同初始条件下达到各自的局部最小值；许多情况下，该电路可以避免一些局部最小值，而找到一个全局最小值。 The structure of switched capacitor circuit with gradient method is established. The common characteristics of steepest descent method, Newton method and quasi-Newton method are analyzed, and the structure of switched capacitor circuit with unconstrained differential optimization is studied. The computer simulation shows that the circuit converges fast and reaches its local minimum under different initial conditions with the change of parameters. In many cases, the circuit can avoid some local minimum and find A global minimum.