This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

ISO1042: ISO1042 VCC2 Bulk capacitance

Part Number: ISO1042

Hello TI,

I am using ISO1042 CAN transceiver to communicate with other controller with my controller. In the datasheet it was recommended to use 4.7uF bulk capacitor at Vcc2. Could you please suggest whats the size of the capacitor that i have to use. I am using 3.3V for Vcc1 and 5V for Vcc2.

Best Regards,

Manoj.

  • Hello Manoj, 

    Thank you for reaching out. Both VCC1 and VCC2 should have 0.1uF capacitors placed close to the supply pins. VCC2 is recommended to have a 4.7uF in addition to the 0.1uF capacitor for robustness of the VCC2 (CANBUS) side supply. 

    I hope this helps. 

    Best,
    Andrew

  • Hello Andrew,

    What is the package size and voltage rating that i have to use for both 0.1uF and 4.7uF. I am using 5V for Vcc2 and the data rates can be upto 5Mbps

    Best Regards,

    Manoj.

  • Hi Manoj,

    The voltage rating and package size are something that you are free to choose based on how much margin you would like to keep and what fits your application better.

    For 5V applications, it is common practice to use capacitors that are 15V or 25V rated to avoid capacitance de-rating.
    For 0.1µF cap, a package size of 0402 or 0603 ceramic capacitors offer lower ESR and are better suited. 4.7µF capacitor can be of any size available in 15V or 25V rating.

    Let us know if you have any further questions, thanks.


    Regards,
    Koteshwar Rao