Browse By Tags

Hi Team,

Why does customer simulate the phase of the OPA855 open-loop gain curve from 180°? But the datasheet starts at 0°

And the open-loop gain is 76dB in the datasheet. Customer found that it is also related to the output…

Hi Team

I am trying to make a balanced detector. In the balanced detector I measured ac current through TIA stage and DC current through current sense amplifiers. I am struggling how can I place the photodiode model in the schematic…

Hello,

i am building TIA with OPA855. Using (and i must use) photodiode with capacity 12pF. Aiming to bandwidth ~100MHz with maximum possible gain (input signal will be in range 0 to 2uA). I expect lot of noise at…

Hi team,

My customer use opa855 as TIA, transimpedance amplification is 10k, output bandwidth is 100MHz, noise is about 10mV.

But from datasheet, the bandwidth should be higher and noise be lower. Could you help to check the schematic…

Can someone explain the below concept, I'm not able to understand it!

"TIA common-mode configurations With the PD configured as shown in Figure 3, the output of the TIA will swing in a negative…

Hello Forum,

I am designing a TIA for photodiode and thought of using the OPA855 as first stage TIA.

My application is as follows.

We will be using a balanced photodetector with theoretically…

Team, 

The user guide has this circuit. Is it meant as a differential in?

Thanks

Viktorija

Hello,

I was wondering if there are any experimental/test data about this device?

I would expect the input capacitance to be affected by the packaging…

Hi Team,

We would like to ask your help regarding the customer concern below.

I noticed some strange behavior in my prototype, maybe you can help me with that, too. I attached the schematic of my prototype. Based on the simulation…

Hello, I am looking for an IC to use as error amplifier in a custom voltage regulator, supposed to perform well at light…

Hi Team

I wanted to know that how can I simulate an AC coupled transimpedance amplifier as shown below. How can I simulate the circuit to check its stability? What are the equations to calculate…

my bro  designed a tia circuit using opa847,the pin has a cap of 25 pf ,two pin consists a parall cap of 50 pf,now i need to make the circuit have 200Mhz bandwidth,and a flat freq…

Hi,

I need to simulate a photodiode with a TIA but i am not sure which TIA should I use. What I need is to amplify the output from photodiode to 5 V and rise time should be as fast as possible…

Hello, 

I would design a amplifier system which frequency bandwidth is 1.5MHz~1500MHz.

The gain required 60dB.

The noise must be very low.

The input signal is around 500uV.

Hi,

Good day.

Our customer would like to use the in their project and they have question described below. I hope you could help us with this.

"ok so my task is:
I have a Photodiode…

Hi,

In 11.2 Layout Example of the datasheet, it is explained that a resistor Riso is inserted in the negative feedback of TIA.
Am I correct in understanding that this is a recommended example…

Hi Team,

The figure is a schematic diagram of the 855 ESD protection diode. The two in the box are on the die. So is the arrow pointed to by the die also?

Why add one more diode(the arrow pointed) between In+ and -?

Add one more question…

Hello,

A customer is having problems with a custom board using OPA855, with the EVM they see much less noise than with the custom board, with exactly the same schematic and parts. This is probably a layout issue that we would like…