GERBER file for the layout

Thomas 11

Prodigy 120 points

Other Parts Discussed in Thread: OPA2846

Dear All,

I am designing the transimpedance amplifier with OPA2846.

I have a big concern for the noise as my light output is extremely weak say 10nA.

So my layout design should be extra clean.

May I have gerber file sample for that OPA2846 for transimpedance amplifier design.

For the power supply, I design switching mode power supply (as we use battery) and then LDO 5V output for power supply noise reduction.

What do I need to take care in terms of layout or in terms of power supply for that noise concern?

Thanks,

Thomas

over 12 years ago

0 Jim Karki over 12 years ago

TI__Expert 4115 points

Thomas,

We do not have a PCB layout and gerber file specific to TIA. The OPA2846 has a free evaluation board that can be ordered at http://www.ti.com/tool/dem-opa-so-2a. It shows proper layout technique and users manual and data sheet describe what to do.

It is important to keep the power supply switching noise out of the signal chain, especially at the frequencies of your signal. I recommend to add LC filter like ferrite bead and local bypass capacitor to low pass filter noise from power supply. If the noise is very high and/or the circuit very sensitive, designers sometimes use a shield (or can) over the components.

0 Thomas 11 over 12 years ago in reply to Jim Karki

Prodigy 120 points

Thanks Jim, you mean shield or can is putting a piece of can and cover the opamp on top of it?

I have no experience in this noise sensitive transimpedance amp circuit. Thanks for the response.

Thomas

0 Jim Karki over 12 years ago in reply to Thomas 11

TI__Expert 4115 points

Thomas,

Yes do a web search on "PCB shield" and you should find a number of products.

Amplifiers

Amplifiers forum

GERBER file for the layout