Forum Post: RE: OP07 thermocouple amplifier
Ranjeet,I suggest measuring the voltage for every node while verifying that the output does not change during the nodal measurements. With every node's value available, the problem will be easier to...
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Forum Post: RE: INA333 Instrumentation Amplifier Current on Reference Pin
Andrew,Your calculation of maximum ~17uA current on REF pin is correct for G=1 but this is not the main reason for keeping the source impedance driving the REF pin below 15ohm. Since any added source...
View ArticleForum Post: RE: OP07 thermocouple amplifier
Thanks will debug..But the circuit is OK I hope.Any other modification is needed. offset input I havent connected. I think I dont need to.
View ArticleForum Post: TIA gain selector for low current measurement
Hello,I'm working into an application to measure low levels of current (1pA or less) and I don't find a solution to implement a variable gain to achieve different ranges of measurements (1pA-1uA). I...
View ArticleForum Post: RE: PGA 309 supply voltages
Hello Haig,The difference between VSA and VSD must remain < 200mV. We don't test the failure modes of conditions which violate our electrical specifications, but a variety of failures might occur....
View ArticleForum Post: RE: INA129 Single Supply operation
Thank you for the reply....Please see the response below for your questions...a) signal is DC.<4% measurement accuracy required.b) source impedance is <200ohm. Signals are driven by opamp.c)...
View ArticleForum Post: Photodiode Preamplifier: Ultra-low Light, High-Speed Detection
Hi everyone,First post, I think...Here is my question: I am trying to amplify a 10-100pA signal (coming from a photodiode array in a TIA configuration). Is it possible to preamplify this signal at...
View ArticleForum Post: RE: TIA gain selector for low current measurement
Hello Albert,As you stated, for 1pA currents you need devices with ultra-low input bias currents (e.g. INA116, OPA129, LMC6001). For such a large load current range you need to change the gain so you...
View ArticleForum Post: RE: INA129 Single Supply operation
Hello Shihab,Thank you for filling in some of the details.Since your source is driven by op amps, I will assume they are low-impedance and balanced. Therefore I think you should look at using the...
View ArticleForum Post: RE: Photodiode Preamplifier: Ultra-low Light, High-Speed Detection
David,For noise reasons you generally want as much gain as possible in the preamp, however this is complicated by the somewhat large capacitance of your detector which will result in peaking of the...
View ArticleForum Post: State Variable Integrator with TI Tina
Hi,I have a personal project to build an audio equalizer base on state variable filter, I have check in TI Tina and using LME49860 opamp (the other candidate is OPA2604), everything looks fine but I...
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Forum Post: RE: opa132 spice model
Francois,I believe you are not simulating open-loop gain properly; AOL needs to be tested using the inverting configuration and post-process using: AOL=Vout/Vos. This is shown in the TINA-TI Reference...
View ArticleForum Post: RE: Photodiode Preamplifier: Ultra-low Light, High-Speed Detection
Alright, thanks again for all the help. Much appreciated! I am going to dig into both books and see if I can come up with something. Seems like I have quite a few options.
View ArticleForum Post: RE: INA333 Instrumentation Amplifier Current on Reference Pin
Hi Marek,Thank you. I am looking at circuit options other than an op amp to drive the REF pin. That is why I would like to know how much current my circuit must source or sink while providing less...
View ArticleForum Post: RE: OP-07CP Output almost constant all the time irrespective of...
Hi, RanjeetI reviewed the datasheet, and i found that the inverting pin is pin2. You should reverse pin 2 and pin 3. And the gain in this circuit, it is R3/R1. Please reconnect it and have a...
View ArticleForum Post: RE: PGA309 Calibration/Software
Hello Ali,Thank you for your interest in the PGA309. I've attached a document which details the mathematics and register writes behind the calibration process. This should be what you're looking...
View ArticleForum Post: RE: ISO124U case temp at 60C ambient -- SOC28 vs DIP16
Rick,You are very welcome.
View ArticleForum Post: RE: OP-07CP Output almost constant all the time irrespective of...
Hello janet, Actually I simply copied and posted. This is like this only. But output is same. What else could be the problem.
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Forum Post: RE: OPA211 noise value
Ken,Attached please find a copy of textbook describing semiconductor physics details behind various types of noise. Bipolar transistor noise section begins on page 750 - see below....
View ArticleForum Post: PGA309 questions
HiWe have some questions for PGA309 from our customer.The customer are evaluating PGA309 on their board.Please give us advice for these questions?1.The conditions required specifications of our...
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