Hi,

I recently bought the ADA4857-2 high speed opamp and the bare-board that allows me to prototype various circuits using the opamp. I want to create a circuit that converts the differential output coming from LTC5586 Zero IF IQ Demod board that I have…

We were using AD8620 Op Amp in our previous application but now want to use the ADA4857 op amp as integrator / charge amplifier. I have compared the following parameters of both the op amps

I am trying to use the ADA4857 to generate a circuit model of a state variable filter in order to compare with measured results.  In our implementation, we are using a single supply (+5V/0) on the ADA4857.  When using the pspice model of the ADA4857 in…

I am trying to do a PSPICE simulation for ADA 4857. I imported the .cir file for this part into orcad. I am not able to tell what each pin is. Can someone help me with this?

Regards,

Sai.

Dear Sir/Madam,

The AD4857-1 datasheet specifies that:

"THE EXPOSED PAD MAY BE CONNECTED TO GND OR VS."

Is this +VS or -VS?

I have split supplies.

Regards Joe

I am running a SPICE simulation (in Altium Designer) using the supplied model for the ADA4857.  If I load the output of the amplifier with anything less than 1Meg or so the output sags very significantly - but I get reasonable performance with a 1Meg load…

I am trying to Configure an ADA4857-2 as an Instrumentation amplifier and I have simulated the circuit in ADS using the model and it is working fine. Now that I am making the schematics,I have encountered two pins which I do not know how to use and they…

I build a Howland current source that can pump bi-directional current up to 1MHz, with maximum output swing to +-10V. The schematic simulated using LTSpice is shown below.

This circuit is also being used in analog dialogue 2009, entitled as,

Difference…

Hi, I do not want to use the power down option of ADA4857-1, so is it ok to left it unconnected (NC) ? or should I pull down this pin to GNDA or connect directly to -VS?

Thanks!

当我把R221、R229断开，REF_2P5V电压也断开，信号发生器输入不带直流偏置的正弦信号，在ADA4857输入端测量时发现有4v的直流偏置电压。在这个基础上，我把C281电容去掉，然后短接，这个直流偏置电压就没了。这个是什么原因呢？