双通道半导体激光电源控制技术

Power control technology of dual-channel semiconductor laser

研制了一种808 nm/635 nm双通道半导体激光器驱动电源,主要由恒流源驱动和温控电路两部分组成。通过12位DA的输出电压对两个通道的驱动电流进行控制,808 nm和635 nm通道的电流驱动范围分别为0-3 A和0-1 A,控制精度分别为0.73 m A和0.24 m A。温控电路由温度传感器、差分放大电路、比例积分微分（PID）控制电路和半导体制冷器（TEC）驱动电路组成,采集的温度信号与设定的温度值进行差分放大后通过硬件PID控制驱动TEC进行制冷制热,实现温度控制以保证输出功率和波长的稳定。在室温23℃下进行应用测试（设定工作温度为25℃）,10 min内,808 nm通道在2.2A驱动时,功率不稳定度为1.805%;635 nm通道在640 m A驱动时功率不稳定度为1.233%。两个通道的P/I特性曲线线性拟合结果的校正决定系数（Adj.R-Square）都大于0.998。

A driver power of 808 nm /635 nm dual-channel semiconductor laser was developed,which is mainly composed of a constant current source and a temperature control circuit. The drive current of two channels is controlled by the output voltage of 12 bit DA. The current range of 808 nm and 635 nm channel are 0 - 3 A and 0 - 1 A respectively,and the control accuracy are respectively 0. 73 m A and 0. 24 m A. Temperature control circuit consists of temperature sensor,differential amplifier circuit,control circuit of proportion integration differentiation（ PID） and drive circuit of semiconductor cooler（ TEC）. After amplifying temperature difference signal,TEC is driven and controlled to cool or heat through PID in order to ensure the stability of output power and wavelength. Application test was carried out at room temperature 23 ℃（ set working temperature at 25 ℃）. Within 10 min,its power instability degree is 1. 805%when drive current of 808 nm channel is 2. 2 A; its power instability degree is 1. 233% when drive current of 635 nm channel is 640 m A. The adjusted determination coefficients（ Adj. R-Square） of linear fitting results are greater than0. 998 for two channels＇ P / I characteristic curve.