Amplifiers forum - Recent Threads

INA239-Q1: Remove the capacitor and the resistors for input filtering.

Shunsuke Yamamoto — Fri, 24 Jul 2026 01:20:59 GMT

Part Number: INA239-Q1

Hi team,

Is it possible for INA239-Q1 not to use input filtering? My customer would like to reduce PCB size of the capacitor and the

resistors for input filtering.

Best regards,

Shunsuke Yamamoto

INA296B: NC Pin

Marco Rojas — Thu, 23 Jul 2026 17:50:02 GMT

Part Number: INA296B
Other Parts Discussed in Thread: INA282

Hi team,

I have a customer with the below question. Let me know what you think, thanks in advance!

"I have a question the INA296 Shunt amplifier:

Pin 4 is marked as NC.

We created footprint and symbol based on the predecessor on our design, INA282:

We have had PCBs made with Pin 4 open.

Question 1: On the INA296 Shunt amplifier, Pin 4 required to be terminated to ground as stated in Table 5-1?

Question 2: If it is required to be connected to ground, why would pin 4 not be called “Ground” and not “NC” to avoid design errors?

My biggest need right now is on the INA296 Shunt amplifier, is Pin 4 required to be terminated to ground?

What would happen if Pin 4 were left Open?"

Marco

LMH3401: LMH3401 input and output offsets observed

Jim Ford — Thu, 23 Jul 2026 16:24:57 GMT

Part Number: LMH3401

Here's part of my schematic, using the LMH3401 as an active balun driving an ADC:

So, 4.7 uF AC coupling capacitor on the - input U51-5, 50 ohm resistor to GND on the + input U51-6, +/-2.5 V rails, Vcm coming from the ADC board and measured to be about +0.7 V, and 40.2 ohm series impedance matching resistors on the + and - outputs U51-13 and -12.

When I put in a 1 MHz sinewave, I measure a peak voltage of 348 mV and trough of 164 mV at U51-5, peak voltage of 252 mV and trough of 144 mV at U51-6, a peak voltage of 528 mV and trough of 8 mV at U51-13, and a peak voltage of 1.28 V and trough of 740 mV at U51-12.

Why am I seeing such DC offsets? They are taking up my ADCs voltage range! I'm particularly puzzled by the offset at U51-5; it is AC coupled by C309, and the rails are symmetric. Shouldn't the center of the sinewave be within a few mV of GND, not ~+250 mV? Does Vcm on U51-2 affect the input offsets? Do I need a 4.7 uF AC coupling cap on the + input U51-6? I thought having symmetric power supply rails would allow DC coupling.

I have 4 channels on my board, but due to software issues, I can't test all 4. I should be able to test another one shortly, when my software engineer arrives. I'll update then.

Thanks for your help!

AMC4311R: AMC4311R's Detailed datasheets cannot be obtained from TI, the access request is still denied.

wei hong — Thu, 23 Jul 2026 08:56:30 GMT

Part Number: AMC4311R

AMC4311R's Detailed datasheets cannot be obtained from TI, the access request is still denied.

AMC1202: Request for Country of Origin Information for the Following Part Numbers

HARUNA IZUMIKAWA — Thu, 23 Jul 2026 07:51:03 GMT

Part Number: AMC1202

Dear TI Japan Customer Support Center,

I hope this message finds you well.
My name is Haruna Izumikawa from SIIX.

I would like to kindly ask if you could provide the country of origin information for each of the following part numbers:

AMC1202DWVR
AMC1350DWVR
AMC23C11DWV
ISO7720FDWVR
ISO7721DWV
LM2940CSX-12/NOPB
LMR54410DBVR
LMT86LPGM
REF35330QDBVR
SN6505BDBVR
SN65HVD82DR
TLV1117LV33DCYR
TLV3201AIDCKT
TLV431ACDBZR
TMP235A4DCKR
TPS70950DBVT
UCC28742DBVR

I apologize for the large number of items.

The destination country is Japan. Since this information is required for registration before placing an order, even general information would be appreciated.

Thank you very much for your kind support.

Best regards,
Haruna Izumikawa

TAS5825MEVM: The access request for LEARNINGBOARD-SW and PUREPATHCONSOLE hasn't been approved even after 4 working days.

zhibing liu — Thu, 23 Jul 2026 06:17:14 GMT

Part Number: TAS5825MEVM

Dear TI engineer, it has been 4 working days since I submitted my application materials and it is still pending. Please approve it for me. I still need time to validate on the project. I have obtained the corresponding development board. Thank you.

AMC1311: Requirement for Texas Instruments Components and Authorized Indian Vendor Details.

Sujeet Kumar — Thu, 23 Jul 2026 05:15:40 GMT

Part Number: AMC1311
Other Parts Discussed in Thread: INA826,

Sr,No.	Manufacturer Part Code	Manufacturer Name	Discreption	Quantity
1	ISO7741DWR	Texas Instruments	ISO774x High-Speed, Robust-EMC Reinforced and Basic Quad-Channel Digital Isolators	10
3	LM393DR	Texas Instruments	Comparator Standard (General Purpose) Open-Collector, Rail-to-Rail 8-SOIC	10
5	TLV1805DBVR	Texas Instruments	Comparator Standard (General Purpose) Push-Pull SOT-23-6	10
6	ESDS311DYFR	Texas Instruments	7.7V (Typ) Clamp 25A (8/20µs) Ipp Tvs Diode Surface Mount SOD-323	50
7	TSD12CDYFR	Texas Instruments	26V Clamp 15A (8/20µs) Ipp Tvs Diode Surface Mount SOD-323	50
8	INA826	Texas Instruments	Instrumentation Amplifier 1 Circuit Rail-to-Rail 8-SOIC	10
9	AMC1311	Texas Instruments	Isolation IC 8-SOIC	10
12	ADS1115IDGSR	Texas Instruments	16 Bit Analog to Digital Converter 2, 4 Input 1 Sigma-Delta 10-VSSOP	10
13	TPS62933DRLR	Texas Instruments	Buck Switching Regulator IC Positive Adjustable 0.8V 1 Output 3A SOT-583	10
14	LM431BCM3/NOPB	Texas Instruments	Shunt Voltage Reference IC Adjustable 2.495V 37 VV ±1% 100 mA SOT-23-3	20
26	TPS63700DRCT	Texas Instruments	Buck-Boost Switching Regulator IC Negative Adjustable -2V 1 Output 360mA 10-VFDFN Exposed Pad	10

BOOSTXL-3PHGANINV: Development Board Selection for 100 kHz Full Bridge Inverter

Davis Hobbs — Thu, 23 Jul 2026 00:05:07 GMT

Part Number: BOOSTXL-3PHGANINV

Hello,

I am considering TI development boards to implement a 100 kHz full bridge inverter. The spec is for 20 V input voltage and about 18 A of current to drive an inductive load for a WPT system. The BOOSTXL-3PHGANINV is close to the spec, but I need a little more current rating and operating the 3 phase inverter as a full bridge feels a bit clunky. Is there another product TI would reccomend for this application? I would prefer platforms designed for the C2000 that require minimal control bring up as the inverter is not the focus of the application. Thanks in advance for your insight.

Thank you,
Davis

THS4531DGKEVM: Convert single ended to differential output

Saurabh Pandey — Wed, 22 Jul 2026 23:42:31 GMT

Part Number: THS4531DGKEVM
Other Parts Discussed in Thread: THS4531

Hi,

I see that this Eval Board takes single-ended input and with unity gain converts to single-ended output (with some resistors and a transformer). Is it possible to use the differential output?

thanks,

Saurabh

TLV7044-Q1: TLV7044-Q1 Pin FMEA Availability

Bob Armbruster — Wed, 22 Jul 2026 19:26:34 GMT

Part Number: TLV7044-Q1

Do we have a pin FMEA for TLV7044QPWRQ1?

TLV2374-Q1: Pin FMEA for TLV2374QPWRG4Q1

Bob Armbruster — Wed, 22 Jul 2026 19:17:54 GMT

Part Number: TLV2374-Q1

Is there a pin FMEA available for TLV2374QPWRG4Q1?

INA126: Lot Trace Inquiry – INA126U – Repeatable 1.36V Dip in Output Transition (Lot 36CHRS vs 85CLCC)

Parth Patel — Wed, 22 Jul 2026 18:56:58 GMT

Part Number: INA126

Hello,

I am a production technician investigating a production issue on PCBAs using the INA126U instrumentation amplifier (SOIC-8), and I'd like help confirming manufacturing details for two specific lots, as well as technical input on a suspected transient response issue.

Issue description:

On a new batch of PCBAs from our board supplier, the INA126U output is expected to be a clean square wave but instead shows a sloped/rounded edge with a repeatable dip to approximately 1.36V mid-transition, instead of a clean, fast edge. This behavior is consistent across new-lot boards and does not appear on our known-good boards (same design, earlier lot).

We've already checked the surrounding board-level components (gain-setting resistor, input filter resistors/caps, and the output reference/offset network) and ruled those out all measured within spec. Swapping the INA126U on an affected board for one pulled from a known good board resolved the issue and the output returned to a clean edge matching our reference unit, which points us toward the device itself rather than the surrounding circuit.

Part and lot details:-

Device: INA126U (SOIC-8)-

Top marking on FAILING/new-lot boards: A BB INA / 126U K / 36CHRS-

Top marking on KNOWN-GOOD boards: A BB INA / 126U K / 85CLCC

Working theories we are trying to rule in/out:

1. Dynamic CMRR/slew-rate mismatch between the two internal front-end op-amps during a fast edge, given the INA126's ~4V/µs slew rate and two-op-amp topology

2. An internal ESD/protection diode conducting momentarily during the edge (the ~1.36V dip level is in the range of one to two diode drops)

3. A board-level difference (gain-setting resistor tolerance, input source edge rate, or added parasitic capacitance) exposing a latent settling characteristic of the part — though as noted above, our own board-level checks did not find a cause here

Questions for TI:

1. Can you decode and confirm the manufacturing date, wafer fab, and assembly site for lot codes 36CHRS and 85CLCC?

2. Were there any process, die revision, or specification changes to the INA126U between these two lots (e.g., slew rate, output stage, or gain-accuracy related changes)?

3. Is a repeatable ~1.36V dip mid-transition consistent with a known internal clamping/protection mechanism on this device, or would that point more toward a board-level cause?4. Is there any known issue or deviation report associated with lot 36CHRS?5. Can you confirm both lots are genuine TI/Burr-Brown product and not from an unauthorized distribution channel?

Thank you for your help.

OPA2180: I'm being asked why opa2180 cannot be held at 200 degC for 4 hours in an oven.

Rick West — Wed, 22 Jul 2026 18:47:37 GMT

Part Number: OPA2180

Hello, The OPA2180 says on the datasheet that the maximum storage temperature is 150C. I'm being asked why that is. Apart from saying the manufacturer says so, what will happen to OPA2180 if we run it, unpowered but mounted to a PCB, in an oven at 200C for 4 hours? Yes, I have asked AI already, but sometimes it gets it wrong and I'd rather not have to defend taking an answer from AI over a real engineer that knows about this. Thanks.

LMV7239: Meaning of the suffix LMV7239M5X/S7002756

Jack Barret — Wed, 22 Jul 2026 14:54:45 GMT

Part Number: LMV7239

Hi!

Could you please help me understand what the suffix S7002756 means? I haven't encountered this before and there is no information about it in the datasheet either.

Best regards,
Jack Barret

OPA858-Q1: OPA838: OPA838: Frequency response in multi-stage TIA configuration

Raz Part — Wed, 22 Jul 2026 12:44:00 GMT

Part Number: OPA858-Q1
Other Parts Discussed in Thread: OPA838, OPA837

Hi,

My previous thread was locked without receiving a response, so I'm reposting my question.

I am experiencing an unexpected frequency response issue in TinaTI simulations when cascading the OPA838 ufter the OPA837 as a TIA. Each individual stage simulates is fine on its own, but the issue occurs when they are combined into a two-stage configuration. I have attached simulations results of each stage alone the the two stages together.
Moreover when using Pspice to simulate the circuit, I have noticed that the DC voltages at the inverting and non-inverting inputs of the second-stage amplifier are unequal.

Could you please provide insight into what might be causing this simulation behavior when these specific stages are combined?

LMC6482: Where to find PCN of LMC6482

Songkan CHEN — Wed, 22 Jul 2026 11:39:38 GMT

Part Number: LMC6482

I find LMC6482IMX/NOPB has Die Revision A and B from the label. I checked with datasheet, no information for Die Revision. So where I could find PCN for this item

INA226: INA226

luo hai — Wed, 22 Jul 2026 10:03:28 GMT

Part Number: INA226

INA226: If an ALERT is triggered, can you read what type of alarm it is? For example, overcurrent protection or overvoltage protection.

INA226: If an alarm is triggered, can we read what type of alarm it is?

luo hai — Wed, 22 Jul 2026 10:01:46 GMT

Part Number: INA226
Other Parts Discussed in Thread: INA238

INA226: If an ALERT is triggered, can you read what type of alarm it is? For example, overcurrent protection or overvoltage protection.

TLV8802: Confusion selecting the right amplifier for 3 electrode electrochemical gas sensor application

Mahendra Gavel — Wed, 22 Jul 2026 08:33:15 GMT

Part Number: TLV8802
Other Parts Discussed in Thread: TLV8812, LPV802, LPV812

Hi,

I am working of desing and development of gas detection portable system for industrial use.

We are using transimpedance amplifiers for biasing and amplification of sensor current which is in nano amperes to microamperes range. The system has virtual ground at 500mv using resistor divider.

Our requirement is a ultra low power amplifier dual channel which has quiscent current under 1uA and lower BOM cost.

We have selected 4 Op-Amps for this purpoes

1. TLV8802

2. TLV8812

3. LPV802

4. LPV812

All these models have suggested application in gas sensing in their datasheet.

There is one specific parameter that varies between these models is input offset voltage from few 100uV to 4.5mV. and I wanted to know if these can create any issue for the sensors or the gas reading accuracy. What exactly can be the effect of this offset voltage in our device? (The sensor readings are zeroed out at the initial bootup of device in software.)

LMH6518: The input ranges when not powered

diverger — Wed, 22 Jul 2026 07:14:06 GMT

Part Number: LMH6518

The DS list the Absolute Maximum Ratings as below:

I have two questions,

For the SPI inputs, it seems they are not related to the VDD. So when VDD = 0, the SPI inputs can still withstand 3.6V?
For the various inputs, such as input common mode voltage, and VCM, are not related to the VDD too. Does it means when the VCC is not powered, the previous stage can still feed signal to it?

Thanks.

INA168: INA139NA/3K or INA139NA/3KG4

Suwitcha Naoniwes — Wed, 22 Jul 2026 07:11:03 GMT

Part Number: INA168

Can you tell me what the difference between INA139NA/3K and INA139NA/3KG4 is

INA139NA/3KG4 is not included in the datasheet.

OPA462EVM: Are R3 and R4 intended to be user-replaceable?

Tezuka Takeharu — Wed, 22 Jul 2026 06:49:00 GMT

Part Number: OPA462EVM
Other Parts Discussed in Thread: OPA462,

Dear Texas Insutruments Support,

I am using the OPA462 EVM for evaluation.

According to the user guide, the default gain is set by resistors R3 (100 kOhm) and R4 (10 kOhm).

I would like to change the amplifier gain by using different resistor values.

Could you please let me know whether R3 and R4 are intended to be replaceable on the OPA462EVM? If so, are there any recommended procedures or precautions when replacing these resistors?

Thank you for your support.

Best regards,

OPA863: OPA863 VIN+ pin floating

Kondo Rin — Wed, 22 Jul 2026 04:11:38 GMT

Part Number: OPA863

When configuring a voltage follower circuit using the OPA863, what is the expected output behavior if the VIN+ pin (pin 3) is left floating?

Will the output gradually drift towards VS+ or GND, or will it just remain floating/unstable?

If it does drift towards the supply rails, I would appreciate it if you could let me know approximately how long it takes to reach that state.

TIDA-00913: More than two FAST observers running at the same time?

Luis Gonzalez — Tue, 21 Jul 2026 19:36:04 GMT

Part Number: TIDA-00913

Hi, I'm using Intanspin-FOC for an application with more than two motors. Motor 1 and 2 are spinning correctly, but when I try to start a third observer using "obj->estHandle = EST_initEst(MTR_3);", it doesn't work. Is there a limit on the number of motors that can be used? Is there a way to use three FAST estimators simultaneously?

TLV1851: Simulation giving values of setpoints different from calculated.

Roosbel Guaya — Tue, 21 Jul 2026 19:02:37 GMT

Part Number: TLV1851

Hi:
I was testing the PSpice for TI simtool and got something a bit strange:

I wanted to look the simple inverting comparator with histeresis, that as the datasheet gives the values, should be like this:

But instead of a conmutation at 1.67... the simtool gives a conmutation at 1.42V.

Maybe I am missing something in my setup? I dont know where the error comes from.

R.