Separating high pass and low pass TIA output bands. - Page 3

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Re: Separating high pass and low pass TIA output bands.
On Tuesday, July 11, 2017 at 3:14:20 PM UTC-4, Artist wrote:
Quoted text here. Click to load it

Look at figure 12 in this document.

http://www.ti.com/lit/ds/sbbs001/sbbs001.pdf  

It's the DC restoration circuit. There will be noise from both A1 and R3 in the feedback loop, so there are trade offs here you need to make.  




Re: Separating high pass and low pass TIA output bands.
On 7/11/2017 4:37 PM, Wanderer wrote:
Quoted text here. Click to load it
I do not have choice regarding the photodiode. That will be chosen by  
someone else. An integrated photodiode tia package is not an option.

--  
To respond to me directly remove sj. from the my email address's domain  
name. This is a spam jammer.

Re: Separating high pass and low pass TIA output bands.
On Tuesday, July 11, 2017 at 7:46:36 PM UTC-4, Pflanze, Stephen wrote:
Quoted text here. Click to load it

I'm not suggesting that you use the OPT301, just the circuit. It's just a TIA with another opamp in the feedback. The OpAmp in the feedback is the low frequency stuff. The output of the forward TIA is the high frequency stuff.

Re: Separating high pass and low pass TIA output bands.
On 7/11/2017 4:52 PM, Wanderer wrote:
Quoted text here. Click to load it

I see that schematic now, and it does look to me to be a better  
alternative to an LC network between the photodiode and two TIAs. This  
has an error integrator in the feedback loop to adjust the TIA's output  
to zero offset.

That method is compatible with the circuit in the article Phil Hobbs  
linked to. I will try it.

Thanks for this.

--  
To respond to me directly remove sj. from the my email address's domain  
name. This is a spam jammer.

Site Timeline