Study Of Dual-wavelength Laser Treatment Instrument Control Circuit Based On Sopc

Laser, attributed to it's unique biological effects, has attracted a lot of attention in medical research, and laser treatment also has been used widely in clinical areas. The stability, reliability and intelligence of the laser drive and control system directly decides laser diagnostic accuracy, the clinical effect and safety of laser treatment. Therefore, there is urgent market demand for the high performance medical laser drive and control system.This topic has designed a new medical laser drive and control system, the key points are as follows:1. The drive of laser sets the power amplifier LT1970 as the core, and it provides primary power output. After boosted by the P channel MOSFET, the current drives the laser. The switch mode power supply with high efficiency and high power serves as the power supply of the device and supply the energy for the MOSFET. The circuit design includes features such as thermal shutdown, over current protection, precise current limit and so on.2. Laser temperature control is operated by the closed loop feedback system which consists of TEC, thermistor and the op amp. The voltage on the negative temperature coefficient themistor varies with the temperature of the laser, and serves as the non-inverting input of the instrument amplifier LTC2053, the differential voltage between the non-inverting input and the inverting input is amplified by the LTC2053, then act as the power supply of the TEC. The drive current of the TEC draw from the LT1970 together with a couple of symmetric P/N channel MOSFET, IRF9520 and IRFP250. And it's direction and size affects TEC operational states whether heating or not, and then works for the laser. So, it forms a closed loop control system, makes the laser work stabler.3. The control part adopts the SOPC (System On a Programmable Chip) technology. On the Altera FPGA chip EP2C35F484C8, we take the NIOS II soft nuclear as the CPU, integrate UART IP core and SPI IP core etc, and then generate a system on chip. Based on this system, we can code to The technical solution described in this paper has been successfully practiced, and it has some theoretical and practical value.