Design and realisation of integrated circuit tester
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INTEGRATED CIRCUIT TESTER pdf
Table 2. 3: Characteristics for CMOS The LM741 series are general purpose operational amplifiers. The amplifiers offer many features which make their application nearly foolproof: overload protection on input and output, no latch- up when the common-mode range is exceeded, as well as freedom from oscillations. Some applications of LM741 include: comparators, Multivibrators, DC amplifiers, summing amplifiers, integrator or differentiators, active filters. Figure 2. 13: Pin-Out Description of Lm741
Table 2. 4: Characteristics of LM741 C. THE NE555 This device is a precision timing circuit capable of producing accurate time delays or oscillation. In the time delay or mono-stable mode of operation the timed interval is controlled by a single external resistor and capacitor network .in the a-stable mode of operation, the frequency and duty cycle can be controlled independently with two external resistors and a single external capacitor. The threshold and trigger levels normally are two-thirds and one-thirds, respectively of Vcc. These levels can be altered by use of the voltage control. Applications include: fingerprints, Iris Biometrics, RFID reader. For Vcc=5V, I0H = -100mA l0L = 35mA, V0H = 33V V0L = .1V Figure 2. 14: (a) Pin out Description (b) Image of NE555 Timer
2.3.2. The Optocoupler Optocouplers, also known as opto-isolators, are components that transfer electrical signals between two isolated circuits by using infrared light. As an isolator, an optocoupler can prevent high voltages from affecting the side of the circuit receiving the signal. Transferring signals over a light barrier by using an infrared light-emitting diode and a light-sensitive product, such as a phototransistor, is the main structure of an optocoupler. 35 Figure 2. 1: (a) picture of optocoupler, (b) the symbol of optocoupler Figure 2. 15: Application of Optocoupler In The Common Emitter Mode Circuit diagram showing the practical application of PC817 in the common Emitter configuration is shown below 5 - 1.4 й-=я«=^л =180n Normalizing, we choose 220П In this project, this component is used to electrically isolate the NE555 circuit from the OPAM IC circuits. ■ Electro-optical Characteristics (Ta= 25*C)
Table 2. 5: Electro-optical Characteristics of PC817 2.5 GENERAL ELECTRONIC DIAGRAM The circuit is being drawn in proteus and the program that is to be loaded into PIC18F4520 is written and compiled in MikroBasic PRO for PIC software Download 0.86 Mb. Do'stlaringiz bilan baham: 
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