CN104155896A

CN104155896A - Laser drift quantity feedback control circuit

Info

Publication number: CN104155896A
Application number: CN201410378504.7A
Authority: CN
Inventors: 卓朝旦
Original assignee: FENGHUA YUCHUANG PRODUCT DESIGN Co Ltd
Current assignee: FENGHUA YUCHUANG PRODUCT DESIGN Co Ltd
Priority date: 2014-07-30
Filing date: 2014-07-30
Publication date: 2014-11-19

Abstract

The invention relates to a laser drift quantity feedback control circuit, which comprises a multi-way analog switch, a filter circuit, an analog-to-digital conversion circuit, a DSP microprocessor, a memorizer, a serial port communication chip and a plurality of digital-to-analog conversion circuits, wherein the multi-way analog switch is used for receiving multi-way drift quantity analog signals; the filter circuit is used for filtering the multi-way drift quantity analog signals received by the multi-way analog switch and then sending the signals to the analog-to-digital conversion circuit to obtain drift quantity digital signals; the DSP microprocessor is used for processing the drift quantity digital signals to obtain the controlled quantity and then sending the controlled quantity to the corresponding digital-to-analog conversion circuits to be converted to the controlled analog quantity; the serial port communication chip is used for realizing the communication between the DSP microprocessor and the peripheral equipment; the memorizer is used for storing the controlled quantity obtained through processing of the DSP microprocessor. The laser drift quantity feedback control circuit extends an RAM, an ROM, and external function circuits like a six-way A/D conversion circuit and a four-way D/A conversion circuit, so that the structure is relatively complex, devices like a code translator, an OR gate, an AND gate or a NOT gate need to be used to extend an interface circuit. The control circuit can simplify the circuit, reduce the size of the circuit board and is convenient to debug.

Description

Laser drift amount feedback control circuit

Technical field

The present invention relates to a kind of control circuit that adapts to laser beam drift amount feedback and control, relate in particular to a kind of laser drift amount feedback control circuit, belong to laser drift amount detection field.

Background technology

Laser beam has the remarkable advantages such as brightness is high, good directionality, concentration of energy, often be used as the manufacture field that measuring basis light beam is widely used in precision measurement and equipment, but due to the factor of laser instrument itself and external environment, there is parallel drift and angle drift in laser beam, this is restricted its directional stability, has affected it and has further applied.

At present, the detection of laser drift amount is a kind of application mode during laser beam is measured, the current FEEDBACK CONTROL to laser drift amount has been used conventional control circuit mode, this traditional control circuit comprises the conventional circuit control modules such as simple DSP and storer, the general strong adaptability of sort circuit, but be not specially for laser drift amount Feedback Control Design.

Summary of the invention

In order to overcome the deficiencies in the prior art, resolve the problem of prior art, make up the deficiency of existing existing product in the market.

The invention provides a kind of laser drift amount feedback control circuit, comprise multiway analog switch, filtering circuit, analog to digital conversion circuit, DSP microprocessor, storer, serial communication chip and multiple D/A converting circuit, wherein, described multiway analog switch receives multichannel drift value simulating signal, the drift value simulating signal that described filtering circuit receives multiway analog switch is carried out filtering, then send to analog to digital conversion circuit to obtain drift value digital signal, described DSP microprocessor is processed controlled amount and is sent to corresponding D/A converting circuit to be converted to control simulation amount drift value digital signal, described serial communication chip is for realizing communicating by letter of DSP microprocessor and peripherals, described storer is for storing the controlled quentity controlled variable that described DSP microprocessor processes obtains.

Preferably, above-mentioned filtering circuit is second-order low-pass filter.

Preferably, above-mentioned multiway analog switch is eight to select a multiway analog switch.

Preferably, above-mentioned analog to digital conversion circuit is 16 high-speed parallel AD converter.

Preferably, the SRAM that above-mentioned storer is 128K.

Preferably, above-mentioned DSP microprocessor adopts the fixed DSP of 16 bit widths.

RAM and ROM have been expanded in outside of the present invention, and the A/D on six tunnels conversion He Si road D/A conversion waits external function circuit, complicated structure, need to use code translator or door, and the device such as door, not gate carry out expansion interface circuit.For abbreviation circuit, reduce circuit board volume, and convenient debugging.

Brief description of the drawings

Fig. 1 is structural representation of the present invention.

Embodiment

Understand and implement the present invention for the ease of those of ordinary skill in the art, below in conjunction with the drawings and the specific embodiments, the present invention is described in further detail.

Control circuit taking DSP as core, by orderly combination, completes collection, analysis, processing to drift value signal, and exports feedback control signal, and the formation of hardware circuit as shown in Figure 1.

Forward direction acquisition channel is made up of multiway analog switch, filtering circuit, the mould/number conversion circuit of Fig. 1.According to the needs of control system, Circuits System will be carried out A/D conversion to maximum six tunnel simulating signals successively, be input to A/D converter therefore carry out Jiang Liu road signal successively with eight path analoging switch, in order to reduce the interference of irrelevant HF noise signal to system, after analog switch, add second-order low-pass filter to carry out filtering processing to signal simultaneously.What analog switch was selected is eight selects a multiway analog switch DG408, the calculating parameter that it is main: supply voltage ± 15V, and conducting resistance is lower than 100 Ω, and open and close representative value switching time is 85ns, meets the requirement of system completely.

Tell nano level change in location, require the analog to digital conversion adopting to expect that precision and degree of stability are all more than 0.5mv, and the voltage magnitude scope of photodetection circuit output is: ± 12V, learnt with forming by control system principle, AD adopts scope wider, control ability and the stability of system are better, comprehensive above factor, and that finally choose is 16 bit A/D converter AD976.AD976 is the high-speed parallel A/D converter of a kind of 16, and it has following outstanding feature:

1) the highest proportion can reach 200KHz;

2) minimum sampling resolving power 0.3mv;

3) input voltage range is ± 10V;

4) single power supply of+5V.

5) transformation result parallel output, chip internal contains sample/hold circuit and Three-State function; The data of conversion can one time 16 bit parallels outputs, also can read at twice by BYTE signal, like this can be easily and 16 or 8 s' single-chip data bus interface;

Storer, serial communication and the DSP microprocessor of Fig. 1 form microcontroller circuit.System requires real-time drift value to be carried out to FEEDBACK CONTROL in feedback control procedure, this has proposed higher requirement to the treatment effeciency of system on the one hand, also to ensure on the other hand the precision of FEEDBACK CONTROL, Given this, select a fixed point Digital Signal Processor (DSP) Tms320F240 of C2000 series of TIX as the microprocessor of system.DSP is the device of processing a large amount of signals with digital signal, have the fields such as the features such as abundant hardware resource, improved parallel organization, data-handling capacity at a high speed and powerful order set are widely used in communicating by letter, space flight, Industry Control, radar, satellite because of it, the principal feature of this kind of chip is as follows:

(1) adopt improved Harvard structure.

(2) order set adopts stream line operation.

(3) there is special hardware multiplier.

(4) storer adopts the inside and outside two-layer configuration of sheet.

(5) use special DSP instruction.

(6) adopt the quick instruction cycle.

Tms320F240 is the fixed DSP of 16 bit widths, the width of its data and address is 16, CPU frequency of operation is 20MHz, peripheral circuit frequency of operation is designed to 10MHz, the cpu instruction cycle is 50ns, in sheet, provide FLASH ROM that 16K can repeat burning and the RAM of 544 Word, sheet outer extendible 64KROM, 64KRAM, 64KI/O and 32K Global Memory.

Need special software and operate cumbersome owing to DSP in-chip FLASH ROM being carried out to burning, and in its sheet, the RAM of 544 WORD can not meet the demand that system will be processed mass data, system has extended out the SRAM of 128K, and wherein 64K is the program space, and 64K is data space in addition.In the program of control circuit being made to artificial debugging downloads to SRAM by the jtag interface of DSP, move, only in the time of practical application just by burning program in the FLASH ROM of DSP.

The embodiment of the above is preferred embodiments of the present invention; not limit specific embodiment of the invention scope with this; scope of the present invention comprises and is not limited to this embodiment, and the equivalence that all shapes according to the present invention, structure are done changes all in protection scope of the present invention.

Claims

1. a laser drift amount feedback control circuit, it is characterized in that: described circuit comprises multiway analog switch, filtering circuit, analog to digital conversion circuit, DSP microprocessor, storer, serial communication chip and multiple D/A converting circuit, wherein, described multiway analog switch receives multichannel drift value simulating signal, the drift value simulating signal that described filtering circuit receives multiway analog switch is carried out filtering, then send to analog to digital conversion circuit to obtain drift value digital signal, described DSP microprocessor is processed controlled amount and is sent to corresponding D/A converting circuit to be converted to control simulation amount drift value digital signal, described serial communication chip is for realizing communicating by letter of DSP microprocessor and peripherals, described storer is for storing the controlled quentity controlled variable that described DSP microprocessor processes obtains.

2. laser drift amount feedback control circuit according to claim 1, is characterized in that: described filtering circuit is second-order low-pass filter.

3. laser drift amount feedback control circuit according to claim 2, is characterized in that: described multiway analog switch is eight to select a multiway analog switch.

4. laser drift amount feedback control circuit according to claim 1, is characterized in that: analog-digital conversion circuit as described is 16 high-speed parallel AD converter.

5. laser drift amount feedback control circuit according to claim 1, is characterized in that: the SRAM that described storer is 128K.

6. laser drift amount feedback control circuit according to claim 1, is characterized in that: described DSP microprocessor adopts the fixed DSP of 16 bit widths.