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  1. #1
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    What are the applications of opamp 741?

    Hi

    I hear a lot about op amp 741, wat is exactly SO GOOD about this op amp and why is it always being used, is it that special?
    Also, can this op amp be used for applications like ultrasonic receiver circuits or an automatic gain control (AGC), etc and why?

    Thanks

    •   Alt11th February 2004, 23:50

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    op-amp 741

    Hi,

    I started to learn electronic 25 years ago. LM741 or uA741 was one of the cheepest OPAMP of the market with no special features. It was available everywhere, so if you wanted to build something witch include an OPAMP (at home or at school), you was able to find it in every electronic shop. Every electronic magazine (like elektor) magazine used it for their publication. Today, this OPAMP is old-fashioned on a technical point of vue, but every people like me, who started analog electronic many year ago, think 741 when there is a question about OPAMP. It is a kind of affection fot it, with a lot of souvenir.



  3. #3
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    op-amp741

    LM 301 is a better alternative with low noice what i felt



  4. #4
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    gain bandwidth product 741

    741 is probably the first opamp ic popularized. Its 3-stage design reprensents the essencial of modern opamp topology. Thus it serves an excellent turorial to beginners.



  5. #5
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    op amp 741 applications

    The previus amplifier was the 709 which required external parts. It also initially cost $75 US back then which was more than one month rent on a flat. The 741 was the next one and it required no external parts except for the type of circuit you used with it. It used lateral PNP transistors which limited the bandwidth. The 709 actually had better bandwidth and was available for some time after the 741. The 709 also had better resistance to radiation which was necessary in space satellites.

    Both of these were designed by the famous Widlar of National Semiconductor. Widlar was very fond of drink at the time which got him finally sacked. There is a funny story about him when he changed jobs. He drove to work after drinking and accidentally went to the previous company. He failed to apply the brakes in time when parking and drove into the lobby through the large glass window and door. This further irritated his former employer.



    •   Alt20th February 2004, 06:43

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    ic 741 features

    Quote Originally Posted by Vicountboo
    Hi

    I hear a lot about op amp 741, wat is exactly SO GOOD about this op amp and why is it always being used, is it that special?
    Also, can this op amp be used for applications like ultrasonic receiver circuits or an automatic gain control (AGC), etc and why?

    Thanks
    Actually there is nothing special about 741. What it is special is that it is general purpose op-amp with considerable bandwidth handling. You can do anything (for the beginer/easy stuff) with uA741 where power is not primary objective but learning op-amps is. It is used in industry where power is not a really concern at all.

    Do not expect also precision etc. using uA741. Great for learning op-amp circuits amplifiers/active filters...etc.

    Not to mention its cost is redicusly low. It is like coffee beans. Price in world market is very low.



    •   Alt20th February 2004, 23:47

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  7. #7
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    unity gain bandwidth 741

    Hello, is there anyone have a formula to calculate the output voltage vary of Op-amp 741 if the temperature change from 15C to 40C?



  8. #8
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    741 op amp alternative

    Quote Originally Posted by flatulent
    The previus amplifier was the 709 which required external parts. It also initially cost $75 US back then which was more than one month rent on a flat. The 741 was the next one and it required no external parts except for the type of circuit you used with it. It used lateral PNP transistors which limited the bandwidth. The 709 actually had better bandwidth and was available for some time after the 741. The 709 also had better resistance to radiation which was necessary in space satellites.

    Both of these were designed by the famous Widlar of National Semiconductor. Widlar was very fond of drink at the time which got him finally sacked. There is a funny story about him when he changed jobs. He drove to work after drinking and accidentally went to the previous company. He failed to apply the brakes in time when parking and drove into the lobby through the large glass window and door. This further irritated his former employer.
    Hah ohh I did not know this story. Bob Widlar is however a great electrical engineer. He designed the first integrated opamp the 709 when he was at Fairchild. Later he moved working for National.

    So he did brake the window glass of Fairchild offices then? Great! ohh



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    op amp741

    Features of LM741

    Excellent Speed: 8 V/s Typ
    Low Noise: 11 nV/√Hz @ 1 kHz Max
    Unity-Gain Stable
    High Gain Bandwidth: 6.5 MHz Typ
    Low Input Offset Voltage: 0.8 mV Max
    Low Offset Voltage Drift: 4 V/C Max
    High Gain: 500 V/mV Min
    Outstanding CMR: 105 dB Min
    Industry Standard Quad Pinouts

    General Description

    The OP-471 is a monolithic quad op amp featuring low-noise, 11nV/(root)Hz Max at 1kHz, excellent speed, 8V/s typical, a gain-bandwidth of 6.5MHz, and unity-gain stability.

    The OP-471 has an input offset voltage under 0.8mV and an input offset voltage drift below 4V/C. guaranteed over the full military temperature range. Open loop gain of the OP-471 is over 500,000 into a 10k Ohm load insuring outstanding gain accuracy and linearity. The input bias current is under 25nA limiting errors due to signal source resistance. The OP-471's CMR of over 105dB and PSRR of under 5.6V/V significantly reduce errors caused by ground noise and power supply fluctuations.

    The OP-471 offers excellent amplifier matching which is important for applications such as multiple gain blocks, low-noise instrumentation amplifiers, quad buffers and low-noise active filters.

    The OP-471 conforms to the industry standard 14-pin DIP pinout. It is pin compatible with the OP-11, LM 148/149, HA4741, RM4156, MC33074, TL084 and TL074 quad op amps and can be used to upgrade systems using these devices.

    For applications requiring even lower voltage noise the OP-470, with a voltage density of 5nV/(root)Hz Max at 1kHz, is recommended.



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    op amp 471

    741 is a general purpose op-amp with simple circuite and its costs is very low so it is use more for usual circuit and teaching and by this way it get famous.



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    automatic gain control opamp

    741 is a general usage AMP OP, nothing special about it, for specific applications reuiring low noise and low distortion, other kind of aplifiers are required.



  12. #12
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    dave fullagar 741

    Consider that 741 was the first internally compensated monolithic OpAmp. Its 30 pF compensation capacitor (making the OA stable at unity gain) ocuped a big area in the chip and was a technological innovation.
    Z



  13. #13
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    gain bandwidth, 741 op-amp dip

    Yes, 741 is no special design any more. But going back to 1960s, that's really a masterpiece. 741 is officially designed by Dave Fullagar in Fairchild with some improvements (the most important ones are inside compensation and short current protection.) though it's a successor to Widlar's work.

    The pioneering and wild Bob Widlar!



  14. #14
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    cmrr of a lm 741 ic

    a very special thing about opamp in general is that,u can set gain according to ur need simply,its gain band width product is 1 maga,so i don't think so that it can be used for the applications u suggest



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