Isolation forum - Recent Threads

ISO1050: ISO1050 CANBUS Waveform issue

Yang Wu — Fri, 06 Mar 2026 06:18:39 GMT

Part Number: ISO1050

Hi Team,

We meet the ISO1050 CANBUS waveform issue, I creat this post to let customer can add more background, issue description etc.

Thanks.

Best regards.

SN6507: Design of a Push Pull Converter SN6507 based

Berlioz Taka — Thu, 05 Mar 2026 12:25:58 GMT

Part Number: SN6507

Hello,

I am working on a design of a push-pull converter for generating from an input voltage of 24V (+-6V) an isolated 5V / 2W for a stepper motor servo drive. The design should take the variation of the input voltage into account and adjust the duty cycle accordingly to keep the output stable. The transformer I intent to use for my purpose is the one I attached to this writing (750319695 from Würth Elektronik). The Design should run at 1MHz switching frequency.

what would please a design solution from you based on the SN6507 to fullfil my requirements?

thank you

750319695.pdf

Thank you

ISO7742TB-Q1: ISO7742 not driving Isolating transformer

digilog — Wed, 04 Mar 2026 23:21:56 GMT

Part Number: ISO7742TB-Q1
Other Parts Discussed in Thread: ISO7742

I have designed a PCB using the ISO7742TBDWRQ1 and the Wurth 760390015 transformer and have followed the data sheet and application notes on the design but the ISO7742 pin 1 and pin 2 do not oscillate and are fixed at 3.3v.

The power supply to the device is 3.3V and I have verified this on the board.

I have checked all connections and layout and cannot see any obvious problems. Each of my boards contain 2 of these circuits and I have so far tested 2 boards and non of the ISO7742 devices are operating.

The only thing I can see is that at the moment the INA, INB are floating and measure about 3V but according to the data sheet this should be OK?

DO you have any ideas as to why these are not working?

ISO7742.pdf

ISO7762DWEVM: Current Limits

Alexander Fitzgerald — Wed, 04 Mar 2026 22:42:26 GMT

Part Number: ISO7762DWEVM

Hello,

What are the output high and low current limits for the ISO7762DWEVM?

Thanks

ISOW1412: Clarification on ISOW1412DFMR

Dineshkumar Jebastin — Wed, 04 Mar 2026 17:01:32 GMT

Part Number: ISOW1412

Hi team,

We are from LTTS.We are currently working on the industrial module project.On the old module we were using the ISO3086TDWR but it has separate transformer and LDO.To Make the design simple we are going to ISOW1412DFMR .So we need a clarity on whether we can use this RS485 instead of the old one .

Thanks,
Dinesh.

ISOM8110-Q1: circuit review

prema R — Wed, 04 Mar 2026 12:44:56 GMT

Part Number: ISOM8110-Q1
Other Parts Discussed in Thread: ISOM8113

We are using ISOM8110DFSRQ1 in our design. We have connected a 24V signal to pin 1. Please let us know if any concern in this circuit.

ISO1212: ISO1212 bidirectional input design

Jensen Huang — Wed, 04 Mar 2026 10:19:10 GMT

Part Number: ISO1212

As the datasheet mentioned diagram as below,

First: What the Cin position is better? Refer to the figure 8-16, I think the Cin is design for filter then why not put the Cin after Rthr? What other purpose does it have?

Second: Continuing the question1, reference circuit as below.

As the mentioned, we need a bidirectional input design, then filter also needed for two inputs so does Rthr can be divide by 2 then put at input side?

Third, If we also need a TVS to prevent EMS , we can put it at where?

SN6507: Simulation Webench

Venkata Rami Reddy Vempati — Tue, 03 Mar 2026 19:14:24 GMT

Part Number: SN6507

Hi Team,

I'm unable to perform the simulation for the SN6507DGQRQ. Could you please provide any available simulation files or support (Webench, TINA, or PSpice)?

Regards,

Rami Reddy

ISO1410: Failure analysis of ISO1410BDWR

Masaoka Tsubasa — Tue, 03 Mar 2026 06:40:45 GMT

Part Number: ISO1410

No.2603002.xlsx

Thank you for your continued support.

This is Masaoka from Mitsubishi Electric, Fukuyama Works.

Regarding the above subject, a failure of ISO1410BDWR was detected during the production process. The symptom is the same as the one for which we previously requested a failure analysis: when we examined the electrical characteristics under the conditions you provided earlier, an abnormality was observed in the output waveform of pin 3 (see attached Excel).

We previously requested a failure analysis from your company for this issue, but the request was declined.

We would like to identify the root cause. Until you are able to accept the failure analysis request, what additional verifications or investigations should we carry out?

Thank you in advance for your assistance.

Best regards,
Masaoka
Mitsubishi Electric, Fukuyama Works

UCC15241-Q1: Inquiry Regarding UCC15241-Q1 leakage current(?) issue

JeongWoo LIM — Tue, 03 Mar 2026 01:51:45 GMT

Part Number: UCC15241-Q1

Hello,
I am a power conversion system engineer currently using your UCC15241‑Q1 device in our designs.

Since the newly released UCC15241‑Q1 became available, we attempted to use it as the power supply for our gate‑driver circuitry. While the basic power delivery and gating functions appear to operate without issues, we observed an unexpected phenomenon: the DC‑link capacitor of the main power conversion circuit begins charging through the gate‑driver board.

Even when only a 24 V input is applied to the UCC15241‑Q1, with the gate board connected to the main circuit, the DC‑link capacitor charges up to nearly 100 V.
Based on my initial assessment, I suspect that leakage current through the galvanic isolation may be contributing to this behavior.

I am sharing the schematic of our design below and would greatly appreciate your review and feedback.
(For reference, our gate driver uses the UCC21717, and this issue did not occur before changing the power supply device.)

Thank you in advance for your support, and I look forward to your guidance.

Best regards,
Jeongwoo Lim

ISO1042-Q1: schematics review

prema R — Mon, 02 Mar 2026 17:02:02 GMT

Part Number: ISO1042-Q1

we are using ISO1042BQDWQ1 in our Retarder ECS design. WE have provided 120 ohms termination as an option depending on whether external termination is present or not in the device connected to our CAN. Please let us know if any concerns in this schematics.

ISO1412DWEVM: The power dissipation related

Hridya TV — Mon, 02 Mar 2026 09:00:02 GMT

Part Number: ISO1412DWEVM

Dear Team,

We are using ISO1412DW IC in our control electronics system for communication. We would like to know how the power dissipation is calculated. We are using 5V at rxr side and 3.3V at the MCU side. In this case, how can we interpret the power dissipation in the IC?

ISO7741: RF susceptibility of the ISO7741FDW

Warren — Thu, 26 Feb 2026 21:55:39 GMT

Part Number: ISO7741
Other Parts Discussed in Thread: ISO6441

We discovered that the ISO7741FDW is susuceptable to radiated fileds at 1.2GHz and 2.4GHz. A signficant amount of effort was put into tightening the shielding of the electronics encloser and filtering all I/O, but we have not been able to reliably solve the issue. We replaced the isolator with the equivilent Skyworks isolator and have had reliably passing results with no upsets. We would like to know if there are known susceptabilies with the ISO7741FDW. My best guess is that the carrier used for signal transmission must be close to 1.2GHz, and the threat is jamming the transmitted signal. There is an advertised new replacement part on TI's web site, the ISO6441. This is advertised as "EMI robust". Would this part have a better chance of passing radiated susceptability testing?

ISOW1412: CISPR 32

Hori Shota — Thu, 26 Feb 2026 14:27:04 GMT

Part Number: ISOW1412

Hi team,

Since the ISOW1412DFMR and ISOW1412BDFMR are said to be CISPR32 compliant, could you please share the radiated emissions test results for the 1 GHz to 6 GHz range with 3.3V input and 3.3V output? I couldn't find any.

Best Regards,

Shota

SN6505B: Current sensing on GND pin

Larry Gunseor — Wed, 25 Feb 2026 17:28:24 GMT

Part Number: SN6505B
Other Parts Discussed in Thread: SN6501

Need to know if it's possible to monitor current for the SN6505B transformer driver by putting a current sense resistor between Pin 4 and GND. If you do this does it effect the operation of the IC. If a resistor can be used between Pin 4 and GND, what is the max value that could be used. Looking to use a 1 Ohm resistor but could use a smaller value.

ISOM8710: ISOM8710 Input side maximum reverse current leakage value.

Ben van den Bergh — Wed, 25 Feb 2026 11:02:42 GMT

Part Number: ISOM8710

Dear forum members.

From the datasheet SLLSFO4C Table 7.1 the maximum input reverse voltage is 5V.
From the datasheet SLLSFO4C Table 7.9 the maximum input reverse current is 10uA.
We have a implementation where the input to the ISOM8710 will be driven using a constant curren diode and also a series diode (The diode is to protect the CCD from reverse polarity amongs others).

However due to the above spesifications does this imply that the absolute worst case reverse leakage of the series diode must be less than 10uA (Across temperature, voltage and process variations)
To protect the ISOM8710 input circuit?
Alternativley we could also add an aditional very low leakage diode in parallel across pins 1 and 2 of the ISOM8710's input.
This however will unfortunately add another part to the BOM.
In short did we interprete the datasheet spesification regarding input reverse current correctly?

Thank you

ISO7021: Can i use this isolator for PWM signal of 100khz

SRAVAN KUMAR VEESAM — Tue, 24 Feb 2026 09:01:44 GMT

Part Number: ISO7021

Hi,

I would like to confirm whether the ISO7021 isolator can be used for isolation from a 3.3V logic side to another 3.3V logic side. The PWM signal frequency is 100 kHz, and it is generated from the TMS320F28379DPTPS.

If this device is suitable, could you please let me know how much input current it will draw from the MCU pin?

If it is not suitable for this application, kindly suggest an alternative isolator part number.

Thank you.

Best regards,
Sravan

ISOM8110: Are there any noise standards that it meets?

Shinichi Inoue — Tue, 24 Feb 2026 04:42:13 GMT

Part Number: ISOM8110

Dear Specialists,

My customer is interested in ISOM8110 and has a question.

I would be grateful if you could advise.

---

The data sheet states that it is modulated using OOK.
Does it meet EMC standards?
Can we assume that the ISOM118x also meets ISO11452-2?

Are there any other noise standards that it meets?

(Previously, ADI products using OOK isolation devices failed to meet radiated field strength standards in the GHz band.)

---

I appreciate your great help in advance.

Best regards,

Shinichi

SN6507-Q1: SN6507: Best way to enable EN/UVLO from a 3.3V PIC (VCC=12–21V)

Sebastian Cardona Ramirez — Mon, 23 Feb 2026 21:45:56 GMT

Part Number: SN6507-Q1
Other Parts Discussed in Thread: SN6507

Hi TI E2E team,

For the SN6507 (VCC = 12–21V), what is the best/recommended way to drive the EN/UVLO pin from a 3.3V PIC GPIO so it is safe for any power-up sequence (e.g., PIC up while VCC is not present) and does not violate the EN/UVLO pin limits?

Thanks,
Sebastian

ISO1450: Clarification on ISO1450/ISO1450B Receiver Output pin current rating

Giorgio Calia — Mon, 23 Feb 2026 16:05:44 GMT

Part Number: ISO1450

Dear TI Support Team,

I would like to clarify the output-current specifications of the Receiver Output (R) pin for the ISO1450 devices.

In the datasheet I found the following parameters for the R pin:

AMR Output current on R pin: ±15 mA
recommended Output current on R pin: ±4 mA

Could you please confirm whether these values are intended as DC, continuous (indefinite time) ratings under the stated VOH/VOL test conditions, or if they represent transient/short‑term maximum capabilities?

For context, I need to assess whether the R pin can directly drive a 50 Ohm transmission line, far‑end‑terminated with 50 ohm resistor (ATE receiver side) with 5V voltage swing (0V to 5V).

thank you
Best Regards

ISOUSB111: Alternative to the ADuM3160 USB digital isolator ISOUSB111 datasheet clarification on VBUS1 and VBUS2 spec when internal LDO is not used

Adam Torma — Mon, 23 Feb 2026 15:19:06 GMT

Part Number: ISOUSB111

e2e,

I’m looking for an alternative to the ADuM3160 USB digital isolator, and identified the ISOUSB111 as the closest match.

I have a question regarding the operating voltages for VBUS1 and VBUS2 on the ISOUSB111. The datasheet specifies an operating voltage range of 4.25 V to 5.5 V.

In my design, we supply 3.3 V ±5% on the non‑isolated side and generate an isolated 3.3 V ±5% on the isolated side. The 3.3 V rails connect to VBUS2/V3P3V2, and the isolated 3.3 V rails connect to VBUS1/V3P3V1.

However, the pin description table states that if 4.25 V to 5.5 V is not available, VBUSx and V3P3Vx should be tied to an external 3.3 V supply. This appears to contradict the recommended operating conditions.

Refer below snapshots for more details.

Could you please clarify the valid operating conditions for VBUS1 and VBUS2 when the internal LDO is not used?

ISO7761: Inquiry about circuit configuration.

deukki shin — Fri, 20 Feb 2026 21:36:04 GMT

Part Number: ISO7761
Other Parts Discussed in Thread: ISO6461

Hello.

I am currently using a gate driver and an isolation IC as follows:

- Gate driver: DRV8350RH

- Isolation IC: ISO7761FDBQR

I have a question regarding the implementation of the nFAULT circuit.

I would like to confirm whether pull-up resistors are required on both sides of the isolation IC for the nFAULT signal.

My understanding is as follows:

Could you please review and confirm?

Thank you.

Best regards,

ISOUSB211: Design Inquiry

Abhishek Manoj — Fri, 20 Feb 2026 11:00:37 GMT

Part Number: ISOUSB211

Hi Team,

I am planning to use the ISOUSB211DPR USB 2.0 isolator in the board design.

The signal flow is as follows: the board receives the USB signal from the host PC through an upstream USB Type-A connector. The signal is then isolated using the ISOUSB211DPR and routed to a 1:4 USB 2.0 hub. Three downstream hub ports are connected to three USB Type-A connectors with ESD protection. The fourth hub port is used for a one-wire interface and is routed through an additional USB isolator, followed by a USB-to-UART converter and a UART-to-one-wire converter before reaching the header.

On the upstream side, the isolator power is derived from the VBUS supplied through the connector. For the isolated side supply, please confirm whether it is preferable to use a 3.3 V rail generated from an isolated DC-DC converter or from the on-board 3.3 V LDO. Additionally, for the downstream USB connectors, an isolated 5 V supply has been provided to prevent interference with on-board circuitry. Please confirm if this approach is appropriate.

The USB interaface block diagram is shared below.

Regards,

Abhishek

UCC12050: Regarding EN pin internal pull-down

teritama — Fri, 20 Feb 2026 10:20:33 GMT

Part Number: UCC12050

Hi team,

Our customer evaluated UCC12050 and observed the EN pin voltage was low on a few devices

when supplied 5V for EN pin through 18kohm resistor.

This issue was found on 3/30 boards. It seems to be caused by failure of internal resistor or protection diode.

So could you please provide the following information?

What is the value of internal pull down resistor? In datasheet, it is noted in 7.3.1 Enable and Disable. However, I can't find detail value.
It seems that there are protection diodes on EN pin for both the positive and negative sides. Is my understanding correct?
Do you have any case information like this issue on this device?

Could please your opinion about above?

Best regards,

teritama

ISO1050EVM: PRODUCT RETURN TO VENDOR B511005872G-9 LFMDTBI-310-01004M WK 08

Tane Diaz — Wed, 18 Feb 2026 20:56:25 GMT

Part Number: ISO1050EVM
Other Parts Discussed in Thread: ISO1050

Hello Team Texas, Good day!

We receive the relese B511005872G-9, TRAKING # 398095741496 with the number invoice 5529821155.

We need your technical assistance because we have observed impedance variations in the MPN component ISO1050DWR.

Please check the PDF attached with the description of the problems in the material.12112530 DC BAD GANTRY.docx (2).pdf

Thank you.

Regards.