LTC6253 - GBP 720MHz, but gain of 10 = BW of ~35MHz??

Hello,

I am trying to design a circuit to achieve a gain of 10 for input signals up to 50MHz. I have looked at LTC6253 as a possibility, since it has quite a large GBP of 720MHz. If my understanding is correct, for a gain of 10, it should handle up to 720/10 = 72MHz

I have done a simulation on LTSpice, of non-inverting op-amp with a gain of 10 but it shows that the bandwidth would end up being around 35Mhz.... See screenshot below. 

The datasheet recommends to use a capacitor in the feedback loop to compensate stray capacitances (C1 in my simulation). Through trial and error I have found this to be around 0.5pF.

It seems there are other parameters I need to consider when selecting my op-amp for this application. Does anyone have any suggestions as to what causes a reduction in effective bandwidth vs what I would have expected from the GBP?

 #

Thanks!

Qbort

Parents Reply Children
No Data