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I'm building a project that needs gain of 1000 (from mV) and bandwidth of 500 kHz. Is there an op-amp (or other parts) with this characteristic? Or maybe it is available in only very expensive parts (like used in NASA or milspec) which has these features? If they are not made of op-amp and chip, what is it made of?

If none, is it more of limit of technology like Moore's limit (in which case, what is the highest gain and bandwidth in any parts available currently) or is it a fundamental limit like Dawes' Limit?

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    \$\begingroup\$ You need gain bandwidth product of 500 million for a single op-amp. And you also need other imortant specs such as offset, noise, etc. But if you split the gain with say 2 op-amps, they both only need gain less than 32 and GBW about 16 MHz. \$\endgroup\$
    – Justme
    Sep 5 at 8:23
  • \$\begingroup\$ so i can find one? what is the chip name? \$\endgroup\$
    – Jtl
    Sep 5 at 8:48
  • \$\begingroup\$ What's the output range? \$\endgroup\$
    – jonk
    Sep 5 at 8:48
  • \$\begingroup\$ i want to build an EMG with 230,000 Hz range \$\endgroup\$
    – Jtl
    Sep 5 at 8:49
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    \$\begingroup\$ If you want this in a single stage, you might need a CFA or a decompensated op amp. If you want this in two or three stages, you can probably use any old op amp. \$\endgroup\$
    – Hearth
    Sep 5 at 12:50

1 Answer 1

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You can look for "precision Op amps" with sub 100µV input offset (for a 1% precision) and with a GBW of at least 16 (so you can get 32 gain at 500kHz) as Justeme has said.

A quick search on TI's website gave me these lists : https://www.ti.com/amplifier-circuit/op-amps/precision/products.html#p480=1;2&p23typ=16;20&sort=p23typ;asc

https://www.ti.com/amplifier-circuit/op-amps/precision/products.html#p2max=0.002;0.1&p23typ=20;63&sort=p23typ;asc

On AD's side :

https://www.analog.com/en/parametricsearch/11094#/p4501=2.5u|100u&p4502=16M|100M

Some come with 2 Opamps in the same IC so it may save you space.

With a peak-to-peak output voltage of 10V you will need a minimum of 31.4 V/µs slew rate for a 500kHz sine wave.

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  • \$\begingroup\$ If I build this on a breadboard, can the breadboard introduce noises? \$\endgroup\$
    – Jtl
    Sep 12 at 11:34
  • \$\begingroup\$ @Jtl Your signal is below 1MHz, the stray capacitance of the bread board won't affect it much (or rather its fundamental frequency). I assume it's a sine wave because you want a 0-to-230kHz range. Also, it's not breadboard "noise" : noise implies a source that radiate or that couples to your signal. Do you have other components on the board ? If your breadboard contains only the amplifier stage, then your set to go. Otherwise, it depends. \$\endgroup\$
    – Rahmany
    Sep 12 at 11:48
  • \$\begingroup\$ Ok. Do you know an electronic design company that can design it for a fee? is there such thing? where exactly? Tnx \$\endgroup\$
    – Jtl
    Sep 12 at 11:54
  • \$\begingroup\$ @Jtl design what ? the amplifier stage ? you can do it yourself ; look into the inverting/non-inverter OpAmp configuration. Otherwise i don't know any company that can do it because this is very basic. \$\endgroup\$
    – Rahmany
    Sep 12 at 12:02
  • \$\begingroup\$ Im building an EMG with range of 1 to 230,000 Hz. What Analog to Digital Converter and Microcontroller should I use? It is hard to build it and even program it. That's why I prefer a company to build it for me with a fee. Isn't there any company that can do custom electronic design for a client? \$\endgroup\$
    – Jtl
    Sep 12 at 12:32

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