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      • Can the Si86xx have 2.5V on one side and 5V on the other side? Can I use it as a level shifter?

        Silicon_Labs | 05/122/2017 | 09:09 AM

        Question

        Can the Si86xx have 2.5V on one side and 5V on the other side?  Can I use it as a level shifter?

        Answer

        Yes, internally the Si86xx has two independent dies that are each powered separately.  Either die can be powered from 2.5V to 5.5V.

         

        Learn more about the Si86xx isolators: http://www.silabs.com/products/isolation/digital-isolators/si86xx-digital-isolators

      • Can the Si86xx have 2.5V on one side and 5V on the other side? Can I use it as a level shifter?

        Silicon_Labs | 05/122/2017 | 09:00 AM

        Question

        Can the Si86xx have 2.5V on one side and 5V on the other side?  Can I use it as a level shifter?

        Answer

        Yes, internally the Si86xx has two independent dies that are each powered separately.  Either die can be powered from 2.5V to 5.5V.

         

        Learn more about the Si86xx isolators: http://www.silabs.com/products/isolation/digital-isolators/si86xx-digital-isolators

      • My VDD or Vout is shorted to ground. I appear to have an over voltage failure. How do I fix this?

        Silicon_Labs | 05/122/2017 | 08:58 AM

        Question

        My VDD or Vout is shorted to ground.  I appear to have an over voltage failure.  How do I fix this?

        Answer

        The most common cause for this is that the output exceeds VDD by 0.5V or VDD exceeded its maximum rating by 0.5V.  If either of these events occurs in your system then an electrical over stress (EOS) has occurred and can cause this type of permanent damage.  To eliminate this issue the best thing to do is determine the source of the event and eliminate it.  If not possible, then add transient voltage suppressors as a safeguard.

      • How is Silicon Labs' new Si86xx digital isolator family different from the Si84xx?

        Silicon_Labs | 05/122/2017 | 08:55 AM

        Question

        Answer

        Silicon Lab's family of ultra-low-power digital isolators are CMOS devices offering substantial data rate, propagation delay, power, size, reliability, and external BOM advantages over legacy isolation technologies. The operating parameters of these products remain stable across wide temperature ranges and throughout device service life for ease of design and highly uniform performance. Recently a new generation of digital isolators, the Si86xx family, was introduced to expand and enhance Silicon Labs isolation portfolio.

         

        As before, data rates up to 150 Mbps are supported, and all devices achieve propagation delays of less than 10 ns. Additionally enable inputs provide a single point control for enabling and disabling output drive. Ordering options include a choice of isolation ratings (1, 2.5, 3.75 and 5 kV) and a selectable fail-safe operating mode to control the default output state during power loss.  All products >1 kVRMS are safety certified by UL, CSA, and VDE, and products in wide-body packages support reinforced insulation withstanding up to 5 kVRMS.

         

        Si86xx Enhancements

        The Si86xx family has several improvements over their lower cost drop-in compatibles Si84xx counterpart:  Specifically the Si86xx family offers:

        • Reinforced insulation withstanding up to 5 kVRMS.
        • Improved regulator for 50x higher PSRR
        • Lower frequency oscillators for lower power operation and even lower EMI
        • Up to 6 isolation channels rated at 5kVRMS
        • Tighter receiver band pass for improved CMTI: 35kV/mS(min), 50kV/mS(typ)
        • Faster output buffer with exactly 50 ohm output termination for tighter output impedance matching
        • Minimum operating VDD = 2.5V
        • Schmitt trigger input for higher input noise rejection
        • Higher ESD rating: 8kV (HBM)

        Figure 1 summarizes the enhancements.

        Isolator-fig1.png

         

        For more information concerning the Si84xx or Si86xx family, see that product datasheet at www.silabs.com/isolation.

         

      • Does Silicon Labs offer SPICE or IBIS models for the Digital Isolator or ISODriver products?

        Silicon_Labs | 05/122/2017 | 08:44 AM

        Question

         Does Silicon Labs offer SPICE or IBIS models for the Digital Isolator or ISODriver products?

        Answer

        Only IBIS models are offered and can be requested on line via a help support ticket (https://siliconlabs.force.com/home/home.jsp).  SPICE models are not provided as they could potentially contain company intellectual property.

      • Si86xx数字隔离器-过压故障

        Siliconlabs | 11/309/2015 | 05:58 AM

        Question

        如果在Si86xx数字隔离器A侧出现过压故障,那么B侧会发生什么?

         

        Answer

        在隔离栅任意侧发生过压故障时,仅会对隔离栅发生故障一侧的内部电路产生损坏。也就是说如果A侧发生过压故障,导致接地或电源短路,那么B侧不会发生故障或短路。B侧仍然会根据数据表中的规定继续操作,多数情况下会返回到默认输出。如果B侧出现故障而不是A侧,情况会一样,A侧会依照数据表运作,而B侧会在"Device Operation"部分“listed as UP”。了解这些情况对于故障检测系统是十分重要的!

      • Si86xx数字隔离器-不同的供电电压/电平转换

        Siliconlabs | 11/309/2015 | 05:54 AM

        Question

        是否可以用单独的或不同的电压来给隔离栅的不同侧供电?

        能否把Si86xx当做电平转换来用?

         

        Answer

        当然可以!

        隔离栅的不同侧是独立供电的。例如,你可以 在VDD1 = 5.0 V, 和VDD2 = 3.3 V下运行设备,反之亦可。只要VDD1 和 VDD2在规定的范围内(请查看数据列表)就可以。

      • Si86xx Digital Isolators - Over-voltage failures

        MikeM | 09/252/2015 | 03:51 PM

        Question

        If I over-voltage Side-A of a Si86xx Digital Isolator, what happens to Side-B?

        Answer

        During an over-voltage failure on either side of the isolation barrier, there will be damage to the internal circuitry only on that side of the isolation barrier.

         

        This is to say that if an over-voltage failure on Side-A causes a short to ground or power, there will not be failure or short on Side-B. Side-B will continue to operate as defined in the datasheet, which most often means returning to its default outputs.

         

        The situation is the same when Side-B experiences failures and Side-A does not: Side-A functions according to the data sheet, where Side-B is listed as UP in the "Device Operation" section.

        Knowing what happens in such a scenario can be crucial for fault-detection systems!

         

      • Si86xx Digital Isolators - Different supply voltages / level shifting

        MikeM | 09/252/2015 | 03:40 PM

        Question

        Can I use separate or different voltages to power each side of the isolation barrier?

        Can I use the Si86xx as a level shifter?

        Answer

        Absolutely!

        Each side of the isolation barrier is powered independently of one another.

        Example: You can run a unit with VDD1 = 5.0 V, and VDD2 = 3.3 V, or vice versa.

         

        So long as VDD1 and VDD2 remain within the specified range (see the data sheet's electrical specification table) you will be fine running them at different potentials.

      • 可以用Si84xx来隔离模拟信号吗?

        Siliconlabs | 09/246/2015 | 07:08 AM

        Question

        可以用Si84xx来隔离模拟信号吗?

         

        Answer

        Si84xx只可以隔离数字信号,但是可以添加附加的board-level元件,从而实现模拟隔离。隔离器输入一侧的模数转换器可用来数字化模拟信号。最后的数据(数字格式)通过数字隔离器发送,并通过隔离器输出一侧的数模转换器转回到模拟格式。有许多技术可以进行A/D和D/A格式转换,包括诸如Delta Sigma, V/F, 和PWM等调制器。这些附加的电路可以是小型而且价格低廉的,比如低价PWM IC可以作为输入侧ADC被添加,而且简单的RC filter可在输出侧作为DAC。