IC-741 (Op-Amp)

It's a slide on IC-741 op-amp...

1. 741 IC Presented By: Nafisa Tasneem (1509032) Showrin Barua (1509048)

2. Introduction An integrated circuit is a semiconductor w afer on which thousands or millions of tiny resistors, capacitors and transistors are fabricated. IC-741 is most commonly used which is an O perational A mplifier. 625 Million Transistors 2

3. History The IC-741 was designed by Dave Fullager of Fairchild Semiconductor in 1968. Genius Creation 3

4. Pin Diagram 1 Offset Null 5 Offset Null The Offset Null pins are used for adjusting offset voltage to obtain better gain 4

5. Pin Diagram 1 Offset Null 5 Offset Null This pin is used to invert the input voltage at 180° 2 Inverting In 4

6. Pin Diagram 1 Offset Null 5 Offset Null This pin does not change the polarity of the given input voltage 2 Inverting In 3 Non Inverting In 4

7. Pin Diagram 1 Offset Null 5 Offset Null These pins are used for positive and negative supply to the IC 2 Inverting In 3 Non Inverting In 4 - Vcc 7 + Vcc 4

8. Pin Diagram 1 Offset Null 5 Offset Null This pin is used for taking output of the IC 2 Inverting In 3 Non Inverting In 4 - Vcc 7 + Vcc 6 Output 4

9. Pin Diagram 1 Offset Null 5 Offset Null 2 Inverting In 3 Non Inverting In 4 - Vcc 7 + Vcc 6 Output 8 Not Connected 4

10. Other Types of 741 IC 5

11. Maximum Ratings Supply voltage Internal power dissipation 500mW Differential input voltage Input voltage Voltage offset null/V- Operating temperature range 0° to +70 ° C Storage temperature range -65° to +150 ° C Lead temperature 300°C Output short circuit Indefinite Supply voltage Internal power dissipation 500mW Differential input voltage Input voltage Voltage offset null/V- Operating temperature range 0° to +70 ° C Storage temperature range -65° to +150 ° C Lead temperature 300°C Output short circuit Indefinite 6

12. Block Diagram Input stage Intermediate stage Level shifting stage Output stage + - o/p i /p This stage provides most of the voltage gain of the op-amp and establishes its input resistance 7

13. Block Diagram Input stage Intermediate stage Level shifting stage Output stage + - o/p i /p This stage uses unbalanced differential amplifier for direct coupling. At the output of this stage DC voltage is above ZERO 7

14. Block Diagram Input stage Intermediate stage Level shifting stage Output stage + - o/p i /p This stage uses level translator circuit. It makes the DC voltage downward to ZERO with respect to ground. 7

15. Block Diagram Input stage Intermediate stage Level shifting stage Output stage + - o/p i /p This stage uses complementary push-pull amplifier. It increases the output voltage swing and raises current supplying capability of the op-amp. It also establishes low output impedance. 7

16. Important Specifications Input offset voltage Input offset current Input bias current Slew rate CMRR (Common mode rejection ratio) 8

17. Important Specifications Input offset voltage : It is the voltage that must be applied between the two input terminals of an op-amp to null the output voltage. V io = V dc1 – V dc2 9

18. Important Specifications Input offset current : It is the algebraic difference of two input currents that flow into the inverting and non-inverting terminals of an op-amp. I io = | I B1 – I B2 | 10

19. Important Specifications Input bias current : It is the average of two input currents that flow into the inverting terminal of an op-amp. I B = (I B1 + I B2 ) / 2 11

20. Important Specifications Slew rate: It is defined as the maximum change of output voltage per unit time and expressed as v/ μ s. SR = | max   12

21. Important Specifications CMRR: Common mode rejection ratio is generally defined as the ratio of differential voltage gain (A d ) to the common mode voltage gain ( A cm ). CMRR = & A cm =   13

22. Important Features Short circuit and overload protection provided . Low power consumption .  Large common mode rejection ratio (CMRR) and differential voltage ranges . No external frequency compensation is required  No latch-up problem. 14

23. Important Applications (1/4) Headphone Amplifier 15

24. Important Applications (2/4) Electronic Thermometer 16

25. Important Applications (3/4) Electronic Fuse 17

26. Important Applications (4/4) Earthquake Detector 18

27. Future We have seen that many sectors have been developed using IC 741. As we are future electronics engineers, the future of IC 741 as well as other electronic devices depend on us. So it is our responsibility to think something different . Who knows it (IC 741) may create a new dimension in modern electronics! 19

28. References i . Op-amps and linear integrated circuits - R amakant A. Gayakward ii. Ctcircuitstoday.com iii. Quora.com iv. Electroschematics.com 20

29. THANK YOU