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/1685456/iso1500-request-for-iso1500-datasheet-correction-and-inquiry-regarding-high-tier-products/6496681Tue, 29 Sep 2026 04:43:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:13e4761a-b7d3-4212-bac8-65879ff9c105Varun KumarHi Lee, Thanks for reaching out. Let me clarify that Figure-33 does not showcase the characteristics of ISO1500 but rather is referred in the datasheet as a typical curve as per RS485 standard (TIA/EIA-485-A). Hence, this has remained in the datasheet and will remain so. We&#39;ve a taken a note for the interest in SSOP-16 package option for higher speed capable devices. We&#39;ll do the business analysis and take a decision accordingly. Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1685730/isom8111-q1-request-to-verify-the-potential-for-magnetic-field-induced-malfunction-of-the-optimal-couplerTue, 29 Sep 2026 01:41:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:f830dff1-eee0-486e-b06a-c8c8e14e2d11HyunGun ChoiPart Number: ISOM8111-Q1 Hello. My name is Choi Hyun-geon, and I am an HW developer at Kyungshin. I have currently designed a switch input circuit using the ISOM8111-Q1. I would like to know if there is a possibility of the optocoupler malfunctioning when a magnetic field is applied to the switch input stage. (This refers to magnetic fields generated by twisted current-carrying wires or by magnetic objects.)Body Electronics &amp; LightingISOM8111-Q1https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1685716/isom8113-package-difference-dfg-v-dfhMon, 28 Sep 2026 23:10:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:f5107259-3abb-4290-b973-b3435da29b37Joe KearneyPart Number: ISOM8113 I am a parts engineer at Northrop Grumman. I am working to get approval to purchase ISOM8113DFGRQ1. Approval was received to purchase isom8113dfhrq1. The only difference I see is the package outline, DFG v DFH. What is the difference between the two?ISOM8113https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1666871/tps25981-schematic-verification-of-tps259813arpwr/6496149Mon, 28 Sep 2026 17:44:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:0cf8a371-3581-46d8-b462-3210394ef9acMani RayHello Irfan, You can select row 16 to &quot;no&quot; then design calculator will not consider any load except output capacitor. Best Regards, Mani.https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1684360/isow1412-layout-emc-review/6495705Mon, 28 Sep 2026 10:38:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:766c9078-c6d9-4031-b250-5dca444f8375Varun KumarHi Jan, Thanks for implementing these changes. Looks good to go. Do let us know how it goes once you test. Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683867/isow7742-q1-output-behavior-if-vio-is-under-logic-voltage/6495702Mon, 28 Sep 2026 10:31:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:062b8724-cfb5-4941-bc86-741bb257b250Varun KumarHi Chase, [quote userid=&quot;464516&quot; url=&quot;~/support/isolation-group/isolation/f/isolation-forum/1683867/isow7742-q1-output-behavior-if-vio-is-under-logic-voltage/6495284&quot;]Is &quot;keeping INx high when VIO is powered off&quot; always violation?[/quote] Yes, it&#39;s always a violation no matter what the duration is. Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1684360/isow1412-layout-emc-review/6495571Mon, 28 Sep 2026 07:54:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:3f3e390f-dad2-41b8-bc42-f6566c51b092Jan RombergHi Varun, thanks for pointing this out. I have implemented option 1.a: R76 and R77 now use a 1206 footprint and are placed on the top layer, overlapping the CMC footprint. Regards Janhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1685456/iso1500-request-for-iso1500-datasheet-correction-and-inquiry-regarding-high-tier-productsMon, 28 Sep 2026 06:44:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:1dcffa17-5073-49ff-bda2-dea7417b2854Lee SungYunPart Number: ISO1500 Hello. I&#39;m writing to request a correction to the datasheet for the ISO1500—the only isolated RS-485 transceiver available in an SSOP package—specifically regarding its maximum data rate. While I understand the ISO1500 is rated for 1 Mbps, &quot;Figure 33: Cable Length vs. Data Rate Characteristics&quot; in the datasheet suggests that it supports 10 Mbps for cable lengths up to approximately 25 feet. Although this 1 Mbps rating was previously confirmed in response to another user&#39;s inquiry eight years ago, the datasheet remains unchanged; therefore, I request that the documentation be updated. Separately, I would also like to ask you to consider developing a product in an SSOP package that supports speeds of 12 Mbps or higher. I intend to use the device for an encoder application, but the current requirement to switch to a larger SOIC package for higher speeds creates space constraints. (Support for 4-wire RS-485 would be an added benefit.) I assume there were technical or cost-related limitations in the past (such as with the ISO USB products), but given the receiver&#39;s speed capabilities in the RS-485 model, I believe it might be feasible to achieve higher speeds by making some modifications to the transmitter section. (Driver&#39;s En/Disable time: 400/250 ns, Receiver&#39;s En/disable time: 20/30 ns) Thank you for reading. S.Y.LeeWired networkingISO1500https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1666871/tps25981-schematic-verification-of-tps259813arpwr/6495387Mon, 28 Sep 2026 04:02:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:08282975-09a3-4b24-a028-3b9e53d1bf34Irfan ShaikhHi Mani, I have used PG signal to turn on the step down load. I just want help to fill the design calculator. Which I am unable to understand. Regards, Irfanhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683867/isow7742-q1-output-behavior-if-vio-is-under-logic-voltage/6495284Mon, 28 Sep 2026 00:40:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:12fe4e00-236b-4aeb-acdb-ca13b757d6a1Chase JeongDear Varun, Thank you for your support. About the answer #1, Is &quot;keeping INx high when VIO is powered off&quot; always violation? (any moment not allowed?) I am asking it because VIO in the waveform is just in the range of absolute maximum ratings. Best regards, Chasehttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1666871/tps25981-schematic-verification-of-tps259813arpwr/6495234Sun, 27 Sep 2026 12:58:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:b1594268-cf8a-4992-a29c-8dd9b1315f75Mani RayHello Irfan, Could you please explain, why do you need all the loads at the time of startup? Use PG signal to turn on the step down load. PG signal will only go high after the VOUT reaches to the VIN level. Best Regards, Mani.https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6494545Fri, 25 Sep 2026 10:00:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:eaedd06d-8a46-4152-9c36-d448c7116e59Varun KumarThe most common advice that I can provide is to connect a series base resistor, Rb, between OUTx and the base terminal. It limits the base current to a safe level for both the driver and the transistor. Calculate Rb using the required saturation collector current Ic, choosing a forced beta/hfe of 10 to 20 to ensure hard saturation Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1684360/isow1412-layout-emc-review/6494538Fri, 25 Sep 2026 09:47:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:5678cd8d-7123-4acb-b3de-6e1d1879c62cVarun KumarHi Jan, Thanks for incorporating the comments. I just have one observation: R76 and R77 footprint in parallel to CMC is defeating the purpose of KOZ and effectiveness of CMC I would recommend two options: Having a large 1206 resistor footprint for R76 and R77 and either overlap it with CMC footprint on top layer itself or take it to bottom layer right beneath the CMC footprint so that the KOZ is maintained Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6494517Fri, 25 Sep 2026 09:19:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:198a522c-55ce-465b-a598-05266b9afb01Nishant GuptaThen for BJT which is option you suggest besthttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6494511Fri, 25 Sep 2026 09:11:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:b26b6253-44e5-4fa8-9e1a-7c273c145d1aVarun KumarNIshant, For operating SEL pin of TMUX, Digital Isolator (ISO6420) is sufficient as it is a digital output (OUTB) to digital Input (SEL) operation. But for BJT, since it is a current controlled device, the OUTx pins cannot be assumed to drive the base of BJT. For VCC2=5V, the max current that OUTx pin can deliver is 4mA. If the BJT&#39;s base requires &gt;4mA, the ISO6420 is not a suitable option. If it is &lt;4mA, then you can go ahead with the ISO6420 in the schematic above. Hope this clarifies your confusion. If you have any specific questions on TMUX1101, request you to raise a new thread so that the right experts can guide you on that. Closing this thread now. Regards Varunhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6494483Fri, 25 Sep 2026 08:21:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:59e7f2cb-297a-46e4-aa7f-8b9465a0c89fNishant GuptaAnalog switch input is also given by FPGA with 3V3 level and 0V to operate switch on and off operationhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6494482Fri, 25 Sep 2026 08:20:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:1bf186c9-5da9-476b-94f4-dafa53740a06Nishant GuptaThanks Aaditya, Is there one single part can be good or resolve the isolation issue for both analog switch and BjT as switch . If one part is not applicable for both application as switch . please provide correct reason and explanation for that . Means 2 channels device can&#39;t be used for both requirement.switch is having VCC of 5V and current of drain to source is approximately in 24-25 mA. And for BJT Open collector configuration is there. So That collector voltage is internally in the electronics circuit we need to drive bjt using base current which is max 1mA but current calculation seems in micro-ampere. FPGA commands given 3V3 level and 0V to turn on and turn off bjt as switch to operate in Saturation and cutoff state. And analog switch tmux1101 is used. Can you please tell in schematic it is correctly done by using digital isolator that Vcc and gnd and sel pin and drain to source that is connected to load is correctly done to separate FPGA ground to the load ground in standby operation. As TMUX1101 is TI part you can refer that . If I am missing something. Thanks &amp; Regards Nishant Guptahttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6494340Fri, 25 Sep 2026 04:41:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:19980b5a-fa60-4e82-b750-7a0db46e0fefAaditya V.Hi Nishant, Thanks for reaching out. Looking at the information you have provided, it seems that you are trying to use an isolated device to drive a BJT and a switch while suppling 24V to the secondary isoalted side. Before we give a part recommendation, I would like to understand your system more. Considering the schematic you have provided, it seems you are trying to drive the BJT and switch. Can you please provide the voltage and current requirements of the switch input, and what are the required collector/base voltage and current for the BJT? In a general sense, the optoemulator might be a great option for the BJ while the digital isolator might be a good option for the switch. Regards, Aadityahttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6494290Fri, 25 Sep 2026 01:35:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:a8c3d8de-de35-4cf9-8f31-d2a7e29d6d35Nishant GuptaYou also give automotive qualified optocoupler isolation option also with part number for this case . So that I can explore in that option also. Also please tell how digital isolator is good option than optocoupler. Also please tell 24V supply at secondary side I can put that option is required in both possibilityhttps://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/1683653/isom8110-ep-optocoupler-selection/6493924Thu, 24 Sep 2026 17:14:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:cafb2cc6-c6f0-47cf-9882-7dfb4399e762Nishant GuptaIs this correct way of operating switches BJT as switch in open collector configuration and analog switch present is TMUX1101 or I need to do something there? And in secondary side I have 24V Is there any part which is avaialble in secondary side can be Vcc2 of 24V or greater ?