采用GaN HEMT的可调窄脉冲激光器驱动电路

为实现纳秒级的输出光脉宽，使用GaN HEMT作为激光器放电回路的开关管。由于GaN HMET的栅极总电荷小，提出使用小尺寸的GaN HEMT建立驱动电路的输入级，响应控制信号，控制放电回路开关管。搭建电路驱动860 nm激光器，并进行测试。放电回路电源电压为12 V，测试结果显示，最大输出光脉宽8.8 ns对应大于8 W的峰值功率，输出最小光脉宽为4 ns。为实现更大的脉宽可调范围，设计另一款电路并测试。该电路实现输出光脉宽大于8.4 ns可调，在电源电压20 V、输入信号脉宽100 ns的条件下，输出光峰值功率可达46 W。电路尺寸分别为10 mm×6 mm和13 mm×11 mm，为实现进一步小型化，对设计的电路提出了集成方法。提出的电路结构简单、容易实现集成且成本低，为窄脉冲激光器驱动电路的设计提供了新的思路。

Adjustable narrow pulse laser drive circuit using GaN HEMT

GaN HEMT is used as the switch of the discharge circuit to achieve nanosecond pulse width. Due to the low total gate charge of GaN HMET, a GaN HEMT with small size is used to build the input stage of the driver circuit to respond to the control signal and control the discharge circuit switch. The circuit is built to drive the 860 nm laser and tested. The power supply voltage of the discharge circuit is 12 V, and the test results show that the maximum output pulse width of 8.8 ns corresponds to a peak power greater than 8 W, and the minimum output pulse width is 4 ns. Another circuit is designed and tested to achieve a larger pulse width adjustable range. The circuit realizes adjustable pulse width greater than 8.4 ns of output light. When the power supply voltage is 20 V and the pulse width of the input signal is 100 ns, the output optical peak power can reach 44 W. The area of the circuit is 10 mm×6 mm and 13 mm×11 mm. In order to realize further miniaturization of the drive circuit, a integration method is proposed for the two designed circuits. The proposed circuit is simple in structure, easy to realize integration and low in cost, which provides a new idea for the design of narrow pulse laser drive circuit.