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ISO1042-Q1: Automotive Iso can bus with SAE J2284-1~5

Part Number: ISO1042-Q1
Other Parts Discussed in Thread: ISO1042

Hi Sir,

Does ISO1042-Q1 could meet SAE J2284? and has stand-by mode like TJA1052i.

I want to replace TJA1052i if possible. thanks~



  • Hi Driscoll, 

    Yes the ISO1042-Q1 can meet SAE J2284. 

    No, the ISO1042-Q1 does not have standby functionality. The power saving of putting the ISO1042 into standby would be minimal, so this channel was eliminated to reduce complexity and allow us to fit into an 8-pin package (DWV package). 

    If we compare the TJA1052i in standby to the ISO1042 with TX held high, you'll see that ISO1042 has lower power consumption. 

    Max Supply Current Side 1 (mA) Max Supply Current Side 2 (mA) Source
    TJA1052i (standby) 5.6 5.6 (page 10 of datasheet, IDD1, IDD2)
    ISO1042 (TX HIGH) 2.1 4.1 (page 9 of datasheet, ICC1, ICC2)

    If you wanted to not transmit on ISO1042, you could either change your software so the TX line transmits HIGH whenever the device is supposed to be in standby, or add an OR gate between TX of the MCU and the ISO1042. The other input to the the OR gate would be considered standby. 

    So other than this standby consideration, the ISO1042 is pin-to-pin compatible with TJA1052i with the following benefits:

    1. Higher working voltage (ISO1042: 1060VRMS, TJA1052i: 800VRMS)
    2. High standoff voltage (ISO1042: +/-70V, TJA1052i: +/-58V)
    3. Wider common mode range (ISO1042: +/-30V, TJA1052i: +/-25V)
    4. Higher CMTI (ISO1042: 85kV/us, TJA1052i: 45kV/us)
    5. Wider Vcc1 range (ISO1042: 1.71-5.5V, TJA1052i: 3-5.25V)
    6. Wdider Vcc2 range (ISO1042: 4.5-5.5V, TJA1052i: 4.8-5.3V)
    7. Smaller package option (ISO1042DWV)

    Please let me know if you have any further questions or need me to better explain anything I've written above. 

    Best regards,