由于可以利用单片功率运算放大器,调节小型直流电机速度的电路,变得简易而便宜。例如,采用象LM13080这样功率器件,在一个简单的负反馈电路中,就能提供比目前市场上出售的许多种速度控制器更好的调节功能。同时,电源瞬变过程的共模抑制也大。如图(a)所示,电路的基准电压由D_2和R_2确定,并经过R_5和C_1滤波。D_1只作为运算放大器输入信号的共模电平换相器用。以运算放大器为基础的负反馈,提供驱动电机的受控电压。因此 Since a single-chip power operational amplifier can be used, a circuit that regulates the speed of a small DC motor becomes simple and cheap. For example, using a power device such as the LM13080, in a simple negative feedback circuit, offers better regulation than many speed controllers currently on the market. At the same time, the common-mode rejection of the power transients is also large. As shown in Figure (a), the reference voltage of the circuit is determined by D_2 and R_2 and filtered by R_5 and C_1. D_1 is used only as a common mode level inverter for the op amp input signal. Op-amp-based negative feedback provides the controlled voltage to drive the motor. therefore