为了解决布里渊光纤传感系统中半导体激光器光源输出功率和波长易受驱动电流和温度影响的问题, 设计了一种高精度恒流驱动和温控电路。该电路利用深度负反馈积分电路对激光器驱动电流进行精密的恒流控制, 同时采用集成温度控制芯片MAX1978控制半导体制冷片的工作电流, 实现对激光器工作温度的精确控制。结果表明, 本设计实现了驱动电流0mA～100mA可调, 电流控制最大相对误差为0.06%, 电流稳定度为0.02%, 温度控制最大误差为0.03℃, 在温控的条件下, 光功率稳定性达到0.5%, 最大漂移量为0.005dBm。该设计实现了对电流和温度的有效控制, 保证了输出光的稳定性。

In order to solve the problem that the output power and wavelength of semiconductor laser light source was easily influenced by drive current and working temperature in Brillouin optical fiber sensing system, high-precision constant current drive and temperature control circuit were designed. Deep negative feedback integrated circuit was used to control the laser drive current precisely. Integrated temperature control chip MAX1978 was adopted to control the working current of semiconductor coolers and achieve the accurate controlment of laser working temperature. The results show that the design achieves the adjustment of drive current from 0mA~100mA. The maximum relative error of current control is 0.06%, current stability is 0.02% and the maximum error of temperature control is 0.03℃. Under the condition of temperature control, the stability of optical power is 0.5%, and the largest drift is 0.005dBm. The design can achieve the effective control of current and temperature and ensure the stability of output light.