Hi,
I need to design an amplifier for 100KHz, 5Vp-p square wave amplifed to 50Vp-p signal with zero crossing (i.e. +25v to -25V)
I am thinking to use OPA2544 Op-amp from TI/Burr-brown with +/-27V supplies. I have attached the circuit here, I do not simulation tools to simulate it.
could any body verify the circuit and post the suggestions?
This part will not do what you want.
Check the data sheet carefully:
The gain bandwidth product is only 1.4MHz - this means that the open loop gain will be only 14 at 100kHz and 1.4 at 1MHz - you are trying to amplify a square wave at 100kHz which means that if you want it to look halfway reasonable on a scope you need a closed loop bandwidth of 1Mhz. You should be looking for an amplifier with a gain bandwidh product more like 1MHz * (10 for the open loop gain) * 10 (for some feedback) - ie a gain bandwidth product of 100MHz !
Your output should be a sqare wave wih 50V pp amplitude at 100kHz - if you allow the rise and fall times to be 10% of the period that means that your output must slew 50V in 1uS - so the slew rate of your chosen chip must be at least 50V/uS but the OPA2544 only offers 8V/us.
The data sheet also shows that the output can only get within 4.2V of the supply rails (at 0.5A output current) so a sensible design margin would be 5V which means you should use +/-30V supply rails.
You don't need simulation tools to choose a part - just check the basics.
When you are ready to simulate you can get a free (and good) simulator from Linear Technology (LT Spice IV on www.linear.com).
If you explained what you need the output to do it might be possible to advise you better.
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