Isolation forum - Recent Threads

ISO1410: CAN USE I2C implementation

Sam Abeysekera — Wed, 23 Sep 2026 19:38:39 GMT

Part Number: ISO1410
Other Parts Discussed in Thread: ISOM8110-EP, ISOS141-SEP

Can I use

ISOS141FDBQTSEP

for I2C implementation

Regards

Sam

ISOW1044: ISOW1044DFMR Very High anomalous VDD current consumption

marco gestri — Wed, 23 Sep 2026 15:38:54 GMT

Part Number: ISOW1044

Dear Sir, we use the ISOW1044DFMR in several of our products. Recently, we encountered two cases involving new boards where, upon initial power-up, the device exhibited excessive current draw on the VDD line (5V). We measured 3–4 ohms between pins 9 and 10. Below please find the schematic. It is always the same use from time. I kindly ask if You can explain the reason. Thank You and best regards.

ISO1640: What does the "BQ" mean in ISO1640BQDRQ1

Tristan Novak — Tue, 22 Sep 2026 18:05:38 GMT

Part Number: ISO1640

https://www.digikey.com/en/products/detail/texas-instruments/ISO1640BQDRQ1/15853911

In the above link, trying to find info on that part number and what the differences are between that and ISO1640DWR.

ISOW1412: Layout EMC review

Jan Romberg — Tue, 22 Sep 2026 12:17:43 GMT

Part Number: ISOW1412

Hello,

I am using the ISOW1412BDFMR as a half-duplex RS-485 interface on a two-layer board. The device runs from a 3.3 V rail, so VDD and VIO are both at 3.3 V.

In a first EMC run, radiated emissions exceeded the CISPR 32 Class B limit by about 3 dB quasi-peak at around 50 MHz. Since 50 MHz is the second harmonic of the 25 MHz power converter inside the device, I suspect the integrated DC/DC is at least part of the problem.

I have since reworked the layout. I reworked the ground pours and the via stitching, moved components closer to the device, shortened the traces on the logic side, and added 1 kohm series resistors in D, R and DE//RE.

Before I build the next prototype, I would like a second pair of eyes on it. Attached are two screenshots, the schematic section around the device and the matching layout section with both copper layers and both ground pours visible.

Is there anything you would change, or anything that might cause trouble?

Thanks in advance.

ISO1042: Alternative ADM3058?

GARETH OU — Tue, 22 Sep 2026 04:34:53 GMT

Part Number: ISO1042
Other Parts Discussed in Thread: ISO1044

Could you please recommend a suitable replacement for the ADM3058?

Thank you for your support.

Best regards,

ADM3058E Datasheet and Product Info | Analog Devices

ISOW1412: ISOW1412 available or ISOW3080?

Jan Romberg — Mon, 21 Sep 2026 14:19:03 GMT

Part Number: ISOW1412
Other Parts Discussed in Thread: ISOW3080

Hello,

we are currently developing a product that uses the ISOW1412. We ran into EMC issues with it and are revising our layout. At the moment there is no stock of the ISOW1412 available. When can we expect it to be back in stock? The situation is delaying our development. Could you also tell us whether this IC will remain available in the long term?

We have also come across the ISOW3080. When will this part be available? It would be an alternative for our development, but we would need to plan it in soon.

Best regards,
Jan

ISO3086: ISO3086 – Feasibility of Using Same Device for Full-Duplex and Half-Duplex RS-485

Mr. PS — Mon, 21 Sep 2026 10:18:10 GMT

Part Number: ISO3086

Hello,

We are considering the ISO3086 isolated RS-485 transceiver for a new design and would like clarification regarding its use in both full-duplex and half-duplex configurations.

Our design requirement is to support both full-duplex and half-duplex RS-485 using the same hardware/device, primarily to maintain a common and redundant design solution.

If yes, what is the TI-recommended connection between the driver (Y/Z) and receiver (A/B) sides for half-duplex operation?

ISOW7742-Q1: Output behavior if Vio is under logic voltage

Chase Jeong — Mon, 21 Sep 2026 07:02:17 GMT

Part Number: ISOW7742-Q1

Dear TI experts,

My customer test ISOW7742-Q1 in their custom PCB.

During the test, customer found the waveform as below. Could you check it?

Turn off the power supply into Vio during operation
The voltage of Vio (Green) is getting lower due to capacitor discharging, and it is maintain as 2.5V~2.7V
The PWM input (Red) is disconnected.
The PWM output (Skyblue) is disconnected in a very short time, and it is floating to 2.5V~2.7V. It is same as Vio.
Turn on the power supply 5V, the output goes to 0V because input is disconnected.

Do you think that the floating output (procedure #4) is normal operation?

I am asking it because I think it is normal that output is going to 0V if Vin is 0V and Vio is under logic voltage.

And obviously output is going to 0V after Vio is applied again.

Could you check that it is normal operation?

Best regards,

Chase

ISO1176T: ISO1176TDWR top markings

Logitech — Mon, 21 Sep 2026 03:08:06 GMT

Part Number: ISO1176T

Hi, good day.

We would like to seek your technical expertise regarding the ISO1176TDWR part marking.

Could you please help us assess whether the marking shown in the photo below presents any potential counterfeit concern or abnormality?

In particular, could you please confirm whether the left or right part represents the authentic TI production marking, especially regarding the font/style of the letter “I”?

We would greatly appreciate your assistance in verifying this.

Thank you.

ISO1050: Application issue.

Reed — Sun, 20 Sep 2026 17:15:53 GMT

Part Number: ISO1050

Hi Team,

Using ISO1050, there are 107 boards with 7 defects. Can you help me check if there are any design issues?

The schematic diagram is as follows:

ISOM8110-EP: Optocoupler Selection

Nishant Gupta — Fri, 18 Sep 2026 19:06:33 GMT

Part Number: ISOM8110-EP
Other Parts Discussed in Thread: ISO7820, ISO6020, ISO6420, TMUX1101

Hello TI Team,

I need to electrically isolate two control signals generated by an FPGA from the switch-side ground.

The current configuration is:

FPGA (3.3 V logic) → isolation device → switch-side circuit

There are two loads on the isolated side:

One analog switch
One BJT used as a switch in an open-collector configuration

Both switches are currently controlled by separate 3.3 V logic signals from the FPGA.

I would like to completely isolate the FPGA ground from the switch-side ground.

Could you please advise on the correct signal path and interface circuit?

My questions are:

Would the following architecture be appropriate?

FPGA GPIO → digital isolator/optocoupler → isolated-side logic → analog switch / BJT switch
For these two 3.3 V control signals, would a dual-channel digital isolator be preferable to a dual-channel optocoupler?
Since one output drives an analog switch and the other drives a BJT in an open-collector configuration, what output/interface circuit should be used after the isolation device?
What TI device would you recommend for this application?
What power supplies and grounds should be used on each side of the isolation barrier to ensure that the FPGA ground and switch-side ground remain electrically isolated?
Are there any important considerations regarding propagation delay, output drive capability, pull-up resistors, and isolation capacitance for this application?

I can provide the schematic and signal timing/frequency if required.

Please suggest the recommended isolation topology and signal path for this application.

ISO7841: ISO7841: Outputs intermittently settle low at power-up while inputs are held high

Mazen A — Thu, 17 Sep 2026 17:51:41 GMT

Part Number: ISO7841
Other Parts Discussed in Thread: ADS8332, TMS320F28035, , ISO6441

We use an ISO7841DW to carry an SPI bus across an isolation barrier. VCC1 is 3.3 V on the processor side (TMS320F28035), VCC2 is 5 V on the isolated side which communicates with an ADS8332 ADC.

On a small percentage of power-ups, the outputs on the isolated side come up low and stay low indefinitely, while the corresponding inputs on the processor side sit at a static 3.3 V the whole time. The inputs are defined, not floating, held high by the F28035's internal pull-ups out of reset. We have also tried adding external pull-up resistors which had no effect on the results. Only fully removing power recovers it. Resetting the processor using its XRS pin does not seem to have any effect on the outcome either.

Replacing the part with a new ISO7841 reduced the failure rate substantially but did not completely eliminate it. A pin-compatible isolator from another vendor eliminated it completely. We have seen these failures across several units, although the failure rate seems to be quite low.

Questions:

1. What determines the output state when VCC2 comes up while VCC1 may still be below its UVLO threshold?
2. Once the output side is in its default state, does it resume tracking the input when the input side becomes valid, or can it stay latched until VCC2 is removed? We see it never resume, over tens of seconds.
3. Is there a VCC1 to VCC2 sequencing or ramp requirement beyond what is in the datasheet?

ISO6520: Clarification ISO6520QDRQ1 can be used for UART and Level translation

Hardware Team — Thu, 17 Sep 2026 08:00:51 GMT

Part Number: ISO6520
Other Parts Discussed in Thread: ISO6521

Hi TI Team,

Our problem statement: We have a processor that uart need to exposed as console port. The UART in the processor is 1.8V domain. And USB to UART bridge is need to be used here for exposing that as console port. We need isolation for this due of any surge occurs will damage the processor .

our plan: processor --> Isolator( if compatabile to do level transalatio from 1.8V to 3.3V)---> USB to UART ic --> USB Mini connector.

So the ISO6520QDRQ1 can also do level translation and can be used for UART? and also please suggest other alternative ideas and share if TI have usb to uart ic with low cost optimisation.

Thanks,
Aravind K B

TIDA-010232: Alternative approach for insulation resistance monitoring in 3-phase AC200V system with automotive temperature requirements

Kyohei — Wed, 16 Sep 2026 10:08:35 GMT

Part Number: TIDA-010232
Other Parts Discussed in Thread: AMC3330, TLV6001, TPSI2140-Q1, ADS1219

Hi team,

We have a customer evaluating an insulation resistance monitoring circuit based on TIDA-010232.

The current design uses:

AMC3330
TLV6001
TPSI2140-Q1
ADS1219

The customer would like to extend the design to a 3-phase AC200V system and is targeting automotive applications.

The main challenges are:

Leakage current of the isolation switch at high temperature (up to automotive temperature range).
Requirement to fit the insulation monitoring circuit into a PCB area smaller than 40mm x 40mm.
Cost reduction compared to solutions using dedicated current sensors such as LEM CDSR.

The customer is concerned that solid-state relay leakage current may affect insulation resistance measurements at high temperature. Therefore, they are considering replacing the isolation switches with mechanical relays.

We would like to understand whether TI has any recommended solution or alternative architecture for this application.

Specifically:

Is there any TI device that can provide lower off-state leakage than TPSI2140-Q1 for insulation monitoring applications at elevated temperatures?
Does TI have a reference design or application note for insulation resistance monitoring in 3-phase AC systems rather than HV DC systems?
Are there any recommended methods to reduce system size while maintaining insulation monitoring performance?
Instead of the electric bridge switching method used in TIDA-010232, would TI recommend a leakage-current-based approach using current sensing?
If a current-sensing approach is feasible, are there any TI current sensing products or reference designs suitable for insulation monitoring that could replace costly magnetic current sensors such as the LEM CDSR series?

Any guidance on the most suitable architecture for automotive-grade insulation monitoring would be highly appreciated.

Best regards,

Kyohei

ISOW1044: Availabilty

rajat lalwani — Tue, 15 Sep 2026 15:42:04 GMT

Part Number: ISOW1044

hello

I have urgent requirement for ISOW1044 part but currently it is not available in supplieres I am getting it for 10X price from few random supplier, Could you please suggest alternet which is available as drop replacement or let me know the supplier which can support or if you can provide 20 sample for testing

please provide soluition

regards

rajat

ISOM8116: Availability of Functional Safety Manual for ISOM8116DFHR

Hori Shota — Mon, 14 Sep 2026 04:56:35 GMT

Part Number: ISOM8116

Hi team,

Could you please let us know whether a Functional Safety Manual is available for ISOM8116DFHR?

If available, please share the document or provide information on how to obtain it.

Best Regards,

Shota

ISO6542: Availability of Functional Safety Manual for ISO6542DBQR

Hori Shota — Mon, 14 Sep 2026 04:54:38 GMT

Part Number: ISO6542
Other Parts Discussed in Thread: ISO6442,

Hi team,

Could you please let us know whether a Functional Safety Manual is available for ISO6542DBQR?

If available, please share the document or provide information on how to obtain it.

Best Regards,
Shota

ISO1432: maximum admissable diode capacitance and Current drawn ICC2 for 115200 bps and 921600 bps baud rates

Lokesh prasad Ganta — Sun, 13 Sep 2026 09:27:27 GMT

Part Number: ISO1432

I am using ISO1432BDW in my design. logic side is powered with same 3.3V which is powering the microcontroller (3.3V_D with respect to GND_D). bus side is powered with isolated 5V (5V_ISO with respect to GND_ISO).
47 ohm series resistance is there on each RS422 line.
what is the maximum allowable capacitance from each line to GND_ISO ? or maximum allowable rise time or fall time ? (I need this information for proper choice of TVS considering diode capacitance)

what is the bus side supply current (Icc2) ?

device can communicate for a Baud rates or data rates of either 115200 bps or 921600 bps

In the datasheet, for the given part number, current consumption and rise time are mentioned for 12Mbps only; not given for 1Mbps or 0.1Mbps. how can i calculate for these data rates.

ISOM8610: ISOM8610 Isolation Performance

Alex Gold — Fri, 11 Sep 2026 11:34:52 GMT

Part Number: ISOM8610

Our design uses a competitor part which is tested, analysed and working but going obsolete. A potential replacement is ISOM8610. It is the only suitable replacement that appears available on the market due to various specification requirements. Functionally, the device behaviour is completely appropriate but the isolation may be a problem and the datasheet is unclear.

For our requirement, we must be able to test isolation withstand for 1400Vdc (or 1000Vrms) for 60s on each production item. This would be seen across the ISOM8610. I have read 8.2.4 in the datasheet and I need to be certain - is the graph implying that the device will withstand >7000Vrms when tested for 60s? And that the 500Vrms or 707Vpk is only if we need the voltage applied over a period of 20/30 years?

Thank you.

ISOM8110: 10 KV isolation!!!

Pritam Malusare — Fri, 11 Sep 2026 10:54:20 GMT

Part Number: ISOM8110

Hi guys,

I read data sheet of ISOM8110, it says that it can give 5KV isolation. My question is can I achieve 10KV isolation by using 2 ISOM8110 is series ??
My application I want to give 10KV isolation in between USB port and device.

ISO1432: Performance Parameters of ISO1432BDW

Hardware Intern — Fri, 11 Sep 2026 04:46:28 GMT

Part Number: ISO1432

I am designing a system using the ISO1432BDW transceiver operating at a data rate at 1 Mbps .To ensure strict adherence to our design margins, could your technical applications team provide guidance on the following operational specifications?

1.What is the recommended maximum differential and single-ended load capacitance at 1 Mbps while maintaining signal integrity ?
2.How does the supply current scale with capacitance loading at 1 Mbps?
3.Slew Rate & Transition Times
4.Driver current at the output

ISO1228: LEDs lighting up when input disconnected in source mode

Brayden Box — Thu, 10 Sep 2026 14:45:52 GMT

Part Number: ISO1228

I have followed the reference design in the ISO1228 datasheet for source/sink mode with the back-to-back LEDs for each channel on the LEDx pins. What I have found, is that in sink mode, the LEDs work properly. However, in source mode, the LEDs are quite bright even when the inputs are disconnected. They do get brighter when an input is active, but why are they on at all? Does the chip have high internal leakage, or could this be the wire break detection current? The LEDs I am using are APHB1608LVBDZGKC. Thanks

ISO3088: ISO3088 SCH confirmation

Vayne Li — Thu, 10 Sep 2026 11:59:34 GMT

Part Number: ISO3088

Hi Teams,

The customer is using ISO3088 for robot applications, which is used for RS485 communication of magnetic encoders. Below is SCH, please help confirm if there are any issues? Thank you.

ISOM8710: ISOM8710 reverse leakage current vs. temperature curve

Benoit Lemieux — Wed, 09 Sep 2026 18:56:32 GMT

Part Number: ISOM8710

Hi Texas Instruments,

I want to design a product that uses the ISOM8710 optocoupler. I am designing the protection stage for the circuit and the datasheet only mentions that the maximum reverse current leakage through the input diode is 5uA @ 25 degrees.

Do you have any additional information in regards to worst-case leakage at higher temperatures? For example, my board can be used up to 85 degrees C. How can I estimate the leakage current at this point? Also, for voltages less than -5V?

Many thanks for the precision.

UCC14341-Q1: Need a similar product as e.g. UCC14341-Q1 but with creepage > 13mm

Fredrik Häggström — Wed, 09 Sep 2026 09:13:31 GMT

Part Number: UCC14341-Q1
Other Parts Discussed in Thread: SN6507, UCC25800

Hi,

Im searching for a solution that can power our gate drivers.
We have a working voltage requirement of 1250V, PD2, and reinforced isolation. The barrier in many of TIs products works for this requirement within 61010-1. However, we require a creepage of at least 12.6mm.

Do you have any upcoming products that solves our issue?

Kind regards