Part Number:OPA564
Hello Everyone,
would you know how to decode a TI lot number?
Part Number OPA561PWP
Lot number 4051241BRB
Thanks
Edward Park
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OPA564: Decode Lot code
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OPA2156: Multiple opamps in parallel?
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INA181: DBV package
Part Number:INA181
Hello,
Our customer use the INA181, have a question about package.
The customer use the INA181 with SOT-23 (DBV) package.
They can not find the Pin 1 Index.
I check the package information on the DS.
It is mentioned "OPTIONAL ORIENTATION MARKING".
If we don't order, there is no Pin 1 index?
Best Regards,
Naoki Aoyama
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OPA2192-Q1: OPA2192-Q1 input common mode range over temp
Part Number:OPA2192-Q1
Hi team,
Could you please help us to check what is the input common mode range for OPA2192-Q1 over the temperature range? datasheet only specified the common mode range under the room temp.
Many thanks
Best Regards,
Wei-Hao
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INA226-Q1: input bias current vs common mode voltage
Part Number:INA226-Q1
Hi,
May i know the reason why the input bias current stop increasing and keep flat when the common mode voltage above 4V?
Best regards,
Dongbao
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THS4551: Parasitic capacitance
Part Number:THS4551
Dear all,
Currently I am designing a single ended to differential front end for an IEPE microphone. The microphone is AC coupled into the front end and amplified/converted using the THS4551 to a differential signal driving a cirrus logic ADC.
In the datasheet of the THS4551 in the section design rules it is stated that the ground/power plane should be opened up around the input and output pins to reduce/prevent parasitic capacitance. Does this mean opening up the top layer ground fill or also the ground and power plane below the THS4551? (For information, my stack up is <Signal top with ground fill> - <GND> - <Power> - <Signal bottom with ground fill>. The THS4551 is on the top layer.)
BR,
Carsten Voort
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THS3061: power-supply decoupling
Part Number:THS3061
Dear Technical Support Team,
Datasheet shows decoupling below.
My circuit has two 0.1-μF in parallel for power supply(Vs).
Should I change from 0.1-μF to 6.8-μF ?
I think that PSRR is not good when noise frequency is high, so I'd like to reduce noise of high frequency with decoupling.
Best Regards,
ttd
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Proper power-supply decoupling
- Use a minimum 6.8-μF tantalum capacitor in parallel with a 0.1-μF ceramic capacitor on each supply terminal. It may be possible to share the tantalum among several amplifiers depending on the application, but a 0.1-μF ceramic capacitor should always be used on the supply terminal of every amplifier. In addition, the 0.1-μF capacitor should be placed as close as possible to the supply terminal.
As this distance increases, the inductance in the connecting etch makes the capacitor less effective. The designer should strive for distances of less than 0.1 inch between the device power terminal and the ceramic capacitors.
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Best Regards,
ttd
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TLV8542: power supply issue
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OPA388: Chopping amplifiers for biopotential measurements
Part Number:OPA388
Hi all,
Are your chopping amplifiers, such as OPA388, are well-suited for biopotential measurements (as EEG,ECG...) ?
Now I`m using conventional JFET-input amplifier with 500nV p-p noise in 0.1-10Hz band, it works normally, but I`m trying to upgrade it to OPA388.
But with OPA388 I have a strange issue: noise level become very high (about 9uV p-p in 0.1-10Hz band, roughly white) when I touch inputs (shorted thru 10k resistors) whith my hand (look at point marked on attached sheme). Without touching this point noise level is almost close to datasheet values.
With conventional JFET op amp this "touching" leads only to DC offset, but noise level remains the same (about 500nV). But with OPA388 there is BOTH offset change and great noise increasing.
I can understand DC offset changing due to EMI rectification because, may be, my body serve as "antenna" for surrounding EMI sources. But why noise level grows? Or, may be, this noise comes from chopping transients? 
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THS4531A: Building Differential Transimpedance amplifier
Part Number:THS4531A
Hello,
I have a circuit which delivers 20uA p2p sine wave current output in Audio Frequency (<40kHz). I want to convert it to voltage so as to measure it's spectral parameters.
I think THS4531 (THS4531A?) is suitable for this application as it has very low input bias current and input offset current.
However, I will need a larger feedback resistor (~10k) compared to the recommended value i.e. 2k ohms. I understand this will lead to stability issues. For this I plan to use a feedback capacitor in parallel with this feedback resistor.
I see that THS4541 and THS4524 are the FDAs whose datasheet mentions "Differential Transimpedence for DAC output" . However they have relatively large Input Bias current (my peak input current will be +/-10uA). Hence I thought THS4531 should be a better candidate for my application.
My doubt is: I don't see "Differential Transimpedance Amplifier" as one of the target applications for THS4531. Is there anything I am missing which makes this FDA a less desirable candidate for Differential Transimpedance Amplifier.
regards,
Ashish
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OPA445: PSRR
Part Number:OPA445
Hello,
I don't understand how to use the PSRR coefficient. The datasheet specifies the PSRR coefficient for a supply voltage Vs of -+ 40V. Do I have to consider an offset voltage Vos due to the Vs variation with respect to -+40V or with respect to a whatever Vs value I choose to use (i.e. -+12V)?
Then, for the AC case, let's assume to have some noise on the supply voltage Vs. Shoud I consider the Vs variation as the peak value of the noise or as the peak-to-peak value of the noise on the supply voltage Vs.
Thanks,
Loris
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OPA548: OPA548 voltage output drop
Part Number:OPA548
HI,
I use the OPA548 for lipo battery simulator in one test equipment that i designing but i have problem to drain more then 1A on the output. My schematics is as in the reference design where i use the potenciometar to set the output voltage and curent limitation. Output voltage should be from 3V to 4,2V and current to 3A. Every time when i put load(resistor 2,7Ohm) on the output, the output voltage drop from 4.2V to 3.12V and the current is 1,4A. This lead to reboot my controler that is target since detect lower battery.
The input voltagfe level that is power the OPA548 is 10V. The gain is 10 (9K and 1K in the loop). The E/S pin it is floating.
According the specification i should be able to drain 3A constantly and 5A in peak, but i can't get to work in my case. It will be goot if i can manage to get 2A constantly in my case. I use the heat sink on the OPA548 so i do not get the termal shutdown.
The final design should be to replacve the potencimetar for output voltage set with pwm and NF filter to get analog voltage and resistors for the current limit.
What could be the reason for this instability on the output voltage and limitation of the current?
Once more to mention that i use the reference design for single power supply from the TI document for OPA548 (SBOS070C –OCTOBER 1997–REVISED JUNE 2015, page 19)
Best Regards,
Vlatko
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OPA549: Over heating of OPA549
Part Number:OPA549
Hello everyone,
I am using OPA549 as a non-inverting amplifier with a gain of 23. It was working fine till now. All of a sudden it seems to be overheated, I am using a large heat sink though.On continuity check,I found pin 8 and pin 10,11 are short circuited.Do you think the opamp is damaged now?
Regards,
Dipendra
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LM331: LM331 low temperature failure mode
Part Number:LM331
Hi,
we are using a circuit that include an LM331. The LM331 is in a circuit reproducing the basic Voltage tot Frequency converter of Figure 14 in the datasheet.
That circuit was used at a temperature of ~-5C which is below the operating temperature range. The person operating it saw a degradation of the output signal as the circuit reach the low temperature. Since then it is not working even after coming back to higher temperature.
Could operating the LM331 at low temperature permanently damage it?
Thanks,
Pierre-Yves
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LMC6482: LMC6482 used for TIA
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OPA2197-Q1: Vo spec question for Negative rail No load condition
Part Number:OPA2197-Q1
I have a question for Vo spec question for Negative rail No load condition.
Data sheet says that 5mV as typ and 15mV as max at Ta =25.
This spec can be applied for Ta -40 to 105 also?
If not, please let us know the spec.
Kasuya
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AMC1211-Q1: AMC1211-Q1 + TLV313-Q1 voltage sensing accuracy
Part Number:AMC1211-Q1
Hello team,
I am considering concept of datasheet AMC1211-Q1+TLV313-Q1 for high voltage sensing in automotive application.
Could you help me to calculate the voltage sensing accuracy?
When sensing the voltage Vsense, I need to know how accurate this solution can sense it. Which factor can affect the voltage sensing reliability?
1. Gain error with input resistance of AMC1211-Q1 (AMC1211-Q1 might have buffer on the input side with 1Gohm input resistance?)
2. Rf+Cf filter?
3. Input offset voltage of AMC1211-Q1
3. Modulator performance of AMC1211-Q1?
4. Gain error with Input impedance of TLV313-Q1 (But there is not gain error and input resistance value in TLV313-Q1 datasheet..)
5. Input offset voltage of TLV313-Q1
Should I consider all of these things? How can I suggest reasonable voltage sensing accuracy to my customer?
Thank you.
Regards,
Oliver Kim
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OPA552: Unstable output
Part Number:OPA552
I use 2 OPA552P. One is configured as a non-inverting amplifier.
The other one is configured as a unity gain buffer. On the breadboard, all OPA552 is connected to + - 30V power supply with a 0.1uF 50V X7R ceramic decoupling capacitors.
A periodic (100Hz) signal is amplified from the first OPA552 and it is connected to the buffer. However, the buffer's output is not stable, showing oscillation.
Whereas, the first amplifying Op Amp doesn't show this problem.
I used Metal Film resistors, by the way.
Even though I lower the amplification, this still happens.
What seems to be the problem? I can't find the reason to observe this unstable oscillation.
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XTR116: current limit issue
Part Number:XTR116
Hi Sir,
Pls reference below circuit, this circuit is work normally and the output voltage (VRL)= 5V (20mA*250ohm). If I swinging the Micro-USB cable, the voltage will increase to 7V and will latch till re-plugin this cable.
I think it may over current protect but don't know how to happen. I also confirm the supply voltage is above 7.5V, you can reference waveform. Could you tall me how to resolve?
thanks~
Regards,
Driscoll
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TINA/Spice/THS4531A: Noise performance in spice models
Part Number:THS4531A
Tool/software:TINA-TI or Spice Models
Hello,
I plan to use THS4531A to build a Fully Differential Transimpedence Amplifier.
To determine the value for stability capacitor in feedback, I have downloaded the spice model for this amplifier.
My question is: Are the noise parameters also present in the spice models ? Can I trust on the Spice noise simulation results done on it ?
regards,
Ashish
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