https://e2e.ti.com/support/isolation-group/isolation/<p style="display:none;">blank</p>en-USTelligent Community 13https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661040/iso1044-iso1044-high-voltage-test-method/6408508Wed, 08 Jul 2026 01:15:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:77a973a6-2943-4500-82a0-b90c1e1a83c2Rain WangHi We speculate that the isolation layout design may also affect the overall isolation capability of the circuit, so we want to test the entire isolation circuit to ensure that the isolation capability can meet the ISO1044 Isolate spec.https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661187/isow6441-high-frequency-noise-and-interference-on-low-frequency-lines/6408456Wed, 08 Jul 2026 00:01:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:7f3f66fe-e2b7-458c-89dd-8eb3a0174eeaYevgeniy Dundukov[quote userid=&quot;605816&quot; url=&quot;~/support/isolation-group/isolation/f/isolation-forum/1661187/isow6441-high-frequency-noise-and-interference-on-low-frequency-lines/6406888&quot;] If you&#39;re unable to share publicly, then let&#39;s connect privately over chat (Sent you the request as well).[/quote] Could you give me a link? It seems none of the ways I use to share images are working for you (even though everything looks fine on my page).https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1662021/iso7763-q1-damaged-inputs/6408446Tue, 07 Jul 2026 23:50:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:8c85d19a-a8bb-424e-9669-58e43d3bef26Igor OrlovichIs there a way to send schematic for review via DM/email? The normal operation is just running 1-30khz pulsetrain through the channels. The conditions described are during power up/shutdown and the current is measured by looking at the voltage drop across series resistor. So just looking at the abs max ratings of the IO pins ESD structures in these caseshttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1662021/iso7763-q1-damaged-inputs/6408239Tue, 07 Jul 2026 21:05:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:f1a45053-63a0-4921-a043-b719ba0cdb9aAaditya V.Hi Igor, Thanks for reaching out. From my understanding, the isolator device is getting some continuous current into the device input pin when the system is shutdown. you can certainly provide schematics for us to review. This will help us also understand your system more. Along with the schematic, can you also provide more information on how you are measuring this current? Can you also explain the operation of the isolator when the system is not in shutdown? Regards, Aadityahttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661922/iso7842-matching-maximum-impulse-voltage-power-supply/6408235Tue, 07 Jul 2026 21:02:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:69df1bc8-4f90-4f6c-b48b-f30e32b286ebAaditya V.Hi Roosbel, Thanks for reaching out. I understand you are looking for a digital isolator with integrated DC/DC with VIMP similar to the ISO7842. we do have a brand new generation of digital isolators with integrated DC/DC such as the ISOW6442. This device has a VIMP of 8kV. https://www.ti.com/product/ISOW6442 If you consider the ISO7842 device, this does not have an integrated DC/DC converter but has a high VIMP voltage. A non-integrated solution would be to use a transformer to power the secondary side of the isolator. Regards, Aaditya Vittalhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661187/isow6441-high-frequency-noise-and-interference-on-low-frequency-lines/6407804Tue, 07 Jul 2026 16:10:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:fa4045e4-8263-4640-9686-d6aa71698341Varun KumarHi Dundukov, Looks like the Images you tried to share above have not been uploaded properly. Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1662021/iso7763-q1-damaged-inputsTue, 07 Jul 2026 14:58:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:8b511ebf-4610-4648-a247-4abbb4284ea2Igor OrlovichPart Number: ISO7763-Q1 Is there a spec for the maximum current the input diode structures can handle? Seeing some parts fail despite having sizeable series resistance on the inputs. During shutdown for a 100ms or so the input on the secondary side is around 0.5V while the power rail is off, but the current into the pin is in 70-150uA range at most. Despite that the pin ends up shorted to ground. Secondly, is there way to get a quick design review to rule out any possible issues causing this?Industrial AutomationISO7763-Q1https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661040/iso1044-iso1044-high-voltage-test-method/6407382Tue, 07 Jul 2026 11:55:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:d3d51c38-a579-4936-a4a9-3c2582203b9eVarun KumarHi Rain, The VISO is stressed across isolation barrier. Hence, as long as the 3KV is applied between GND1 and GND2 of ISO1044, the test is valid. However - Please know that each and every device is production tested for VISO as per UL standard and is mentioned in datasheet as well. So, I&#39;m not sure why you have to test it again. Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661922/iso7842-matching-maximum-impulse-voltage-power-supplyTue, 07 Jul 2026 11:53:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:d2c686e1-268f-4289-bdd1-2c567426d5c4Roosbel GuayaPart Number: ISO7842 Other Parts Discussed in Thread: ISO7742TB-Q1 , ISOW7742-Q1 , ISOW6442 Hi: The ISO7842 has a creepage distance in the DWW format of 14.5mm and a Maximum impulse voltage of 9.8kV in air. Is there a matching isolated power supply for this digital isolator? I am interested in the Maximum impulse voltage, it just fits my needs. And the DWW format makes it easier to make a slit big enough so that the PCB is not the problem. The other isolators that i have seen like the: ISO7742TB-Q1: Maximum impulse voltage 8kV ISOW7742-Q1: I would prefer to use the ISOW7742-Q1 but it does not seem to meet my requirement of a 1.5/50us waveform of 9.8kV in air (PCB slit). Can you please guide me to a matching isolated dc/dc power supply? R.ISO7742TB-Q1ISOW7742-Q1iso7842ISOW6442Test &amp; Measurementhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661341/ucc33420-ucc33420-failure-during-iec-61000-4-2-esd-testing-8-kv-air-discharge/6407297Tue, 07 Jul 2026 10:40:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:294ca2f6-95df-4c0b-9fbb-afda7325a2dcPrateek VermaHi Zbigniew , Pls find the inputs below: The device incorporates chip-level improvements for system robustness, but its on-chip ESD clamps (HBM &#177;2kV, CDM &#177;750V) are for manufacturing protection only — not system-level IEC 61000-4-2 immunity. An 8 kV air discharge on the secondary side injects common-mode transient current through the isolation capacitance of the integrated transformer, which can overstress the VCC/GNDS pins if no external clamping is present. The datasheet explicitly acknowledges sensitivity to IEC 61000-4-x disturbances in harsh industrial environments. Follow these Layout Guidelines for ESD robustness : make sure that each guidelines is followed. Adding a TVS + CMC at the secondary connector entry point before the ESD energy reaches VCC is the most direct mitigation technique that could be used. We do not have any specific documents /App note for IEC 61000-4-2 pass/fail test results for this device&#39;s EVM (UCC33420EVM). But I have provided links to general system -Level ESD protection Guide documents below. Add a common-mode choke on the secondary output to block CM transient propagation toward VCC I didn&#39;t see any specific ESD related issue with this device. But most common solution would be to use TVS diode and CMC. See below application note on ESD Protection :- 1. System-Level ESD Protection Guide 2. IEC 61000-4-x Tests for TI’s Protection Devices 3. ESD Fundamentals Part 2: IEC 61000-4-2 Rating TI’s TPD1E1B04 , for example, has an IEC 61000-4-2 rating of 30kV/30kV Thanks, Prateekhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661491/iso1211-input-voltage-range/6407018Tue, 07 Jul 2026 07:05:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:c5b2550f-fd71-4cdd-a297-cc9a813902c9Varun KumarHi Marvin, Thanks for the inputs. Yes, you&#39;re right about the -60V interpretation but the minimum voltage but the minimum input voltage for which the device can detect a HIGH is close to 9V (that too with RTHR=0Ohm), hence the 5V is not supported by the device. This is also mentioned in datasheet as VIH specification: If customer is using this device for the first time, then I request you to refer following section in datasheet to understand the external component dependency on Voltage thresholds: 8.2.1.1 Design Requirements 8.2.1.2 Detailed Design Procedure Let us know if there&#39;s are any further questions after going through the datasheet sections Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1657132/lmz10505-details-submission---u66-fa-request-pn--53501974-1-car-aco20253161-01/6406993Tue, 07 Jul 2026 06:50:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:258fe1fe-bcdb-45aa-8471-720dd26ca346Andreas MuellerHello Fatin, thanks for providing the Gerber data, but I&#39;m not able to identify the location and involved components of the LMZ10505. Please help to mark it or to extract the relevant sub-section of the layout. Best regards, Andreas.https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661187/isow6441-high-frequency-noise-and-interference-on-low-frequency-lines/6406986Tue, 07 Jul 2026 06:46:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:eb1e906c-adec-4c95-b62e-acaab32be183Yevgeniy DundukovI didn&#39;t take screenshots of the waveforms, but I can do so tomorrow.https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1660849/iso6763-request-for-maximum-input-clamp-current-rating-for-iso6763f-iso6721f-and-iso1640/6406981Tue, 07 Jul 2026 06:41:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:bc999d0c-5a1d-46d3-9343-65e2f5e138ebVarun KumarHi Sang-il, Thank you for your trust in TI Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1660190/tps2663-about-reverse-polarity-protection/6406973Tue, 07 Jul 2026 06:39:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:2dabd53d-01b9-4bef-a659-64645cd94063Bandaru HemanthHi, Sorry for the confusion it&#39;s my bad, Placing UVLO ladder after NFET would create extra complication that is not recommended at all , i had a discussion with my design folks. 1) &gt;300k ohm will solve this issue, if you keep in Mega ohm, it is much more helpful &amp; if you have a BOM you can also use Schottky diode. 2) current R_1 = 750 kΩ still results in a -0.557V, as long as the ladder current is in uA it won&#39;t create any latch up issues. thanks, Hemanthhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1660190/tps2663-about-reverse-polarity-protection/6406953Tue, 07 Jul 2026 06:23:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:185b6b55-f7b8-405f-8e2d-ad91df54ca23Bandaru HemanthI will get back to you by the end of today. thanks, Hemanthhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661187/isow6441-high-frequency-noise-and-interference-on-low-frequency-lines/6406888Tue, 07 Jul 2026 05:40:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:8bec517b-52bf-46e9-b091-f6c670d9376dVarun KumarHi John, Thanks for reaching out. The schematic and PCB links shared above are blocked by our internal security team, hence unable to review it. Can you please share those directly here? - If you&#39;re unable to share publicly, then let&#39;s connect privately over chat (Sent you the request as well). Also, please do share the waveforms clearly showcasing the noise you&#39;ve mentioned above so that we can better understand the nature of the problem here. We need these inputs before jumping into any conclusion and providing further analysis and debug steps. Let us know. Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1657132/lmz10505-details-submission---u66-fa-request-pn--53501974-1-car-aco20253161-01/6406876Tue, 07 Jul 2026 05:35:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:48963e5b-f81a-45fd-b12b-47c902022ce1Fatin NadzirahHi Andreas, Thank you for the assistance. Kindly refer to the attachment for the PCB layout. e2e.ti.com/.../69000997-Gerber-Layer--_2800_1_2900_.docx Additionally, regarding the inquiry- How is the EN signal generated? Kindly refer the response below; Refer to our schematic and measurement the source for +5VDC that similar both pin 1 (VIN) with pin 2 (EN) Generate/provide by external power supply CCA PN: 69000996-012 was standby for +5VDC.https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1661040/iso1044-iso1044-high-voltage-test-method/6406748Tue, 07 Jul 2026 03:56:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:040006f5-9bd7-4bd7-9b66-0c04da2261d2Rain Wanghi Please help confirm if our following testing methods are OK spec:AC 3KV 60shttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1660849/iso6763-request-for-maximum-input-clamp-current-rating-for-iso6763f-iso6721f-and-iso1640/6406654Tue, 07 Jul 2026 02:24:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:6dba9039-3992-44c6-9832-edfc72764943Sang-il NamHi Varun Kumar, Thank you for your detailed response. I reviewed the ISO64xx series you suggested. Unlike the ISO67xx series, it does not have a diode connecting the input terminal directly to the power supply. Although the absolute maximum rating in the datasheet is similarly expressed as &quot;VCCx + 0.5 V,&quot; an additional footnote specifies that it is acceptable as long as it does not exceed 6V. Therefore, if the sole purpose is to prevent device damage—setting aside normal operation during such conditions—I believe this is an excellent solution. As for the ISO1640, I noticed from the datasheet that it is a newer device improved to support hot-swap, unlike the legacy ISO1540. I think it will work well provided that we can limit the line current to an appropriate level. Currently, an immediate replacement is difficult due to low stock and purchase limits for the ISO64xx on the TI store. However, once sufficient inventory becomes available, I think we will use the combination of the ISO64xx series and ISO1640, especially since they are package and pin-compatible. Thank you again for your thorough support. Best regards, Sang-il