WEBENCH® Tools/LM7171: LM7171

There are an A and B version in the TINA V11 library, original national models - looks like the B is downgraded DC specs. less expensive, this is a slew enhance input stage VFA device - quite a few coming out in that late 1990's time frame - great slew rate, but at the cost of higher noise

LM7171 TINA V11 models.TSC

I don’t see LM7171 in TINA-TI library how can I add? Or can you suggest similar Op Amp must be DIP8 thru hole package. I need to amplify 10.7MHz signal. Input is 100mV and output needed up to or close to 2V. If you can sugest any op amp?

Hello Najeeb, 

You can convert the LM7171 Pspice file for use in TINA-TI:

Steps on how to do this can be found here:

Best,

Hasan Babiker

I attached a TINA file with the op amp models in them. 

You only require 68V/usec slew rate, and a gain of 20V/V, 

look at the OPA684 for a +/-5V low power solution. 

Hi, Michael.

How did you calculated that 68V/usec slew rate, and a gain of 20V/V, required for following case? I am trying to learn this is very helpful to select the correct device.

CASE: " I need to amplify 10.7MHz signal. Input is 100mV and output need to 2V." 

I will really appreciate your help.

NAJEEB QURESHI.

Hey Najeeb, 

The gain calculation is pretty straightforward, its just your output over your input voltage. In regards to the slew rate, you can use your bandwidth to estimate your needed rise time using the equation 0.35 / 10.7MHz = 32.71ns. From there you can use your output voltage over your rise time to calculate for slew rate = 61.14 V/us. This rise time to bandwidth equation assumes a single pole rolloff of 20dB/dec, Michael is likely giving more margin in the case of any second-order effects causing faster rolloff (such as the peaking seen in the OPA684 datasheet). 

Best,

Hasan Babiker

Thanks Michael, looks like I was calculating for the small-signal rise time rather than for the peak dV/dT that might be needed.

Best,

Hasan Babiker