성균관대 3학년용

http://pdf.datasheetcatalog.com/datasheet/ChenyiElectronics/mXrywxv.pdf

1N5236 : 0.5W / 7.5V(Forward Voltage)

Google에서 1N5236 pdf 검색

>> 1N5221 THRU 1N5281 datasheet

>> N5236 Datasheet pdf - 0.5W SILICON PLANAR ZENER DIODES ...

둘중 하나 검색 (아래꺼 추천)

아래꺼 누르면

http://www.datasheetcatalog.com/datasheets_pdf/1/N/5/2/1N5236.shtml

여기로 들어와서 검색

---

http://www.electroschematics.com/5004/555-triangle-waveform-generator/

Here the IC NE555 is wired as an astable multivibrator with unequal ON and OFF times. 

불안정 바이브레이터 with 같지않은 ON and OFF times.

The the resistor R1, R2 and capacitor C2 sets the ON and OFF time periods.

The value of these components are so selected that the OFF time is less than 10% of the ON times. 

가 값 of these 부품들은 그렇게 선택됬다. that the OFF 시간은 덜하다. than 10%보다 of the ON타임의.

The asymmetric square wave is available at pin 3 of the IC. The working of the astable multivibrator is given below.

비대칭 사각파는 이용가능하다. at 핀3에서 of the IC의. (출력이다.)

When the power supply is switched ON, 

capacitor C1 starts charging through resistors R1 and R2. 

When the voltage across C1 is above 2/3Vcc the upper comparator inside the NE555 swings to positive saturation and this triggers the internal flip-flop. 

This makes the output (pin 3) of the timer low. 

Now the capacitor C1 starts to discharge through resistor R2 into pin 7 of the IC. 

When the voltage across capacitor C1 becomes less than 1/3Vcc, the lower comparator inside the IC switches to positive saturation and this again triggers the internal flip-flop. As a result the output of the timer( pin 3) goes low. This action is repeated and the result will be a square wave at pin 3 of the NE555. The charging time period (ON time) is given by the equation T1= 0.69(R1+R2)C1 and the discharging time period (OFF time)  is given by the equation T2=0.69R2C1. Read this article :  NE555 as astable multivibrator for a better understanding on NE555 based astable multivibrators..

The assymmetric square wave obtained at the output of NE555 is integrated by the inverting active integrator based on opamp IC uA741. Resistors R3 and R4 sets the gain of the opamp integrator. Resistor R4 in conjunction with capacitor C3 sets the bandwidth. Since the integrator is wired in inverting mode, the sawtooth wavform falls when the timer output is high and rises when the timer output is low. Read this article: Triangular wave generator for a better understanding on opamp integrators.