Design Of Number-adjusted Group Of Series-connected Semiconductor Lasers Driver With Function Of Achieving Noisy Inspection

With the increasing development of application of semiconductor laser, we require more and more power about these LD, while the price of high-power lasers are more and more higher, it appears trend of exponential rise, Therefore, group of series-connected semiconductor,its advantage conventional driver equipment of group of series-connected semiconductor lasers, which is closed loop simulation, although it can control the circuit accurately, the circuit's design is very difficult with only simulation, and it is very difficult to maintain, which can not change data with external processor, can not monitoring working conditions of laser tube well.This paper introduces a laser driver which not only has the function to achieve noisy inspection, but also can drive a number-adjusted group of series-connected semiconductor laser. It resolved the problem effectively that output power is not stable, and it can adjust the quantity of the diode. This equipment adopt combination of FPGA and single-chip microcomputer , through using the method which measures noise to check, to discover and alarm in time when there are one or more LD destroyed in the group of series-connected Semiconductor Laser, and ensure the whole system run continuously and reliably.This device mainly receives the data from the A/D converter with FPGA controller. The received data, compared with the initialization, transmits the processing results to the D/A converter. FPGA can control the port circuit such as LED displays,keyboard too, making the system controllable. Hardware circuit design mainly employs modular design approaches, such as constant current source circuit, driving circuit of mosfet, power sampling circuit, V/I conversion circuit and the port circuit of FPGA with A/D converter,D/A converter,LED displays. Nay, we especially increased the slowly startup circuit,protecting-circuit,the temperature control unit in this design aiming at the semiconductor laser′s"delicately". These designs can ensure the driving device to drive the semiconductor laser series-wound group stably, well and truly, reliably and safely.The main contents of thesis are as follows:(1) The thesis introduces the progressing history of the semiconductor laser and its main application. it makes us understand semiconductor laser haply, and simply, it researched operational principle of the semiconductor laser, and expounded damage principle of the semiconductor laser systemic, and then received attention of using semiconductor laser.(2) It design a new kind of laser driver which not only has the function to achieve noisy inspection is designed in this paper, but also can drive a number-adjusted group of series-connected semiconductor laser, and this device adopts many little semiconductor laser in series.(3) The hard module circuit in the design system, including Constant Current Source Circuit, slowly startup circuit, power sampling circuit and V/I conversion circuit, doing some analysis with them. The thesis designs driving circuit and protect circuit in the temperature control unit, analyzes detailed anti-interference measures of the system.(4) Investigating in detail FPGA which is the core controlling implement and it's characteristics, designing and analyzing the connection circuit ,such as A/D, D/A, Monitor and Keyboard, introducing simply the using devices. Introducing the configuration mode of FPGA, describing the state transition of ADC0809 by VHDL,output control of the DAC0832.(5) It makes some analysis and introduction about every functional module hard circuit principle, and makes corresponding theoretical derivation. It introduces programmable resizable array of intelligent controller, provides detailed part of function source program code according to software design requiring and resizable array of function subprogram.(6) Make some experimental analysis and conclusion according to schematic circuit diagram and test result.