半导体激光器驱动电路设计及环路噪声抑制分析

为了防止驱动电流的波动会影响半导体激光器激射波长及发光功率，设计了一款具有较强抗干扰能力的半导体激光器驱动电路。该驱动电路以深度负反馈架构为核心，通过STM32控制器调节输出电流直流信号的大小以及调制波信号的频率与幅值。对整个环路进行一阶人工分析，并且结合Tina-TI仿真引入参数可调的噪声抑制网络，保证目标设置频率下环路响应能力的同时具有较强的抗干扰能力。实验表明，该激光器电流驱动电路对目标频率10 倍频程以上环路噪声的抑制可达到20 dB以上，并且对目标频率的调制波响应良好，频率的输出值与设定值最大偏差为0.001 Hz，控制线性度为0.999 9，直流偏置下驱动电流2 h短期稳定度优于0.005 6%，63 h长期稳定度优于0.011%，激光器功率控制线性度为0.999 4，标准误差为0.092 87。

Design of semiconductor laser driver circuit and analysis of loop noise -suppression

In order to prevent the fluctuation of driving current from affecting the laser excitation wavelength and luminous power, a sinusoidal modulation driving circuit of semiconductor laser with strong anti-interference ability was designed. The driving circuit takes the deep negative feedback architecture as the core, and sends control instructions by serial port. Through STM32 controller, the magnitude of dc signal in the setting voltage as well as the frequency and amplitude of sinusoidal signal were adjusted. First-order manual analysis of the whole loop was carried out, and a noise suppression network with automatically adjustable parameters was introduced by Tina-TI simulation.Experimental results show that the current driving circuit of the laser can suppress the loop noise of more than 10 times the target frequency by more than 20 dB.The maximum deviation between the output value of the frequency and the set value is 0.001 Hz, and the control linearity is 0.999 9. The short-term stability of the 2 hour driving current under dc bias is better than 0.005 6%, and the long-term stability is up to 0.011% at 63 hours. The control linearity of the laser power is 0.999 4, and the standard error is 0.092 87.