Abstract
This work for the profile generator (Waveform Generator) the electric circuit,can have each kind of profile which usually we in the experiment frequently use.Its principle is using 89c51 monolithic integrated circuit external connection d/a converter DAC0832,as well as by transports puts the LM324 chip external connection electric circuit to constitute the I/V switching circuit and the see-saw circuit,thus has four kind of basic profiles,using the nixietube the circuitry which demonstrates the profile type and the frequency.D/A trades the extension uses microprocessor compatible 8 d/a converter DAC0832,high speed,stable,has the good linearity.Transports puts LM324 to constitute the I/V switching circuit and the opposition proportion amplifying circuit,stable,precise.The nixietube is four positive nixietubes,brightness is altogether high.This work's characteristic is may several kind of basic profiles which outputs us through the pressed key choice to want to obtain:Square-wave (Quadrate wave),sine wave (Sine wave),triangular wave (Trigon wave) and saw-tooth wave (Saw tooth wave).May also need the profile through the pressed key choice output the frequency,its scope arrives at 20kHz in 100Hz,the profile precision can satisfy the general exploitation conditions.And the square-wave brings by the 89C51 monolithic integrated circuit interior counter/timer T0 production,because its principle is simple,the precision and the frequency are quite high.The sine wave is divides into a profile cycle 64 spot compositions,obtains the D/A transformation data which through the computation each spot voltage corresponds,becomes a table this data platoon,produces using the procedure table look-up's way,because considers monolithic integrated circuit's process time and the profile accuracy,therefore highest can only have the 1KHz frequency sine wave profile.The triangular wave and the saw-tooth wave procedure is through from Canada with from the data quantity which reduces produces,the profile is quite steady,but the frequency is not very precise.All the data which outputs by the monolithic integrated circuit from 8 d/a converter DAC0832 the digital quantity transforms into the simulation electric current signal,after I/V switching circuit obtained each kind of profile voltage waveform to guarantee its precision,was smooth and is stable.