ADuM14xE Mixed Operation Volta

Hello everyone, how do you do?

Lately, we have been using ADuM5201 to isolate two circuits, provide power supply and to communicate between them.

However, we use the 5V input power to provide 5V on the output, and we are using a AND gate on the output of a microcontroller port so that it has a high logic level on the adum5201 communication input, that is, using AND gate to convert the signal from 3V3 to 5V.

I would like to know if  ADuM142E can operate with mixed operation voltage in both sides, if I could power VDD1 with 3V3 and VDD2 with 5V, or VDD1 with 5V and VDD2 with 3V3, so that I would have:

  • logic levels on side 1 VIL1<(0.3*VDD1) = VIL1 < 1V and VIH1>(0.7*VDD1 ) = VIH1 > 2V3, with VDD1=3V3;
  • logic levels on side 2 VIL2<(0.3*VDD2) = VIL2 < 1V5 and VIH2>(0.7*VDD2) = VIH2 > 3V5, with VDD2=5V.

and the opposite too, in such a way that it is no longer necessary to use a AND gate to increase the voltage of the high logic level to communicate with ADuM142E.

OBS: I will provide power supply to the second circuit using a LT8301 flyback converter.

  • +1
    •  Analog Employees 
    on Sep 15, 2021 2:58 AM

    Hi Filipe, 

    I'm not clear on the power rails of the circuit as described, so its difficult to offer guidance... 

    Fortunately the ADuM142E question is easy. Yes, they can operate with mixed voltages. They are CMOS input/output and the levels scale with the local VDDx supply. 

    The LT8301 is certainly one option to provide isolated power to the secondary side. Let me mention that the ADuM5201 has the VSEL pin to change the output to 3.3V if that is required. There are also other isoPower devices like the ADuM6422A that can be operated with 5Vin/3.3Vout and have 4 integrated isolated data channels if more channels are required.



  • Hi Jason, thanks for replying my question.

    I'm glad to hear that ADuM142E can operate with mixed voltages.

    About ADuM5201, we're using 2 ADuM5201 to provide enough current to the secondary side, and we also need 5V and 3V3 in the secondary side. Beside, it is difficult to buy ADuM5201 with our suppliers, so we're trying to get other options, and it seems the LT8301+ADuM142E are more cost atractive to us.

    I'll procede with LT8301+ADuM142E, thanks.