AT90CAN128 is the AGND pin electrically separate from GND?

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LS_IPECO
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2018/10/17 03:07:48 (permalink)
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AT90CAN128 is the AGND pin electrically separate from GND?

On page 4 of the datasheet there is a diagram of the processor, at the ADC section the label AGND is used. On page 5 showing the chip pinout PIN63 is labelled as GND (same as pins 53 and 22).
Are these three pins connected on the die? I'm looking at a circuit design which assumes PIN63 is separate, the PCB uses a dedicated ground return for this pin and decoupling components for AVCC and AREF.
All advice appreciated.
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    rodims
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    Re: AT90CAN128 is the AGND pin electrically separate from GND? 2018/10/18 11:38:54 (permalink)
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    I would assume that the pinout labelling on page 5 is simply wrong, it should show pin 63 = AGND instead of GND and I don't expect it to be internally connected to GND.
     
    Look into the schematics here and see what Olimex does with AGND and how they labelled pin 63 in the schematics
    https://www.olimex.com/Products/AVR/Development/AVR-CAN/resources/AVR-CAN.pdf
     
    Although Microchip bought Atmel, you usually will not find Atmel users in this "old" Microchip PIC dedicated forum.
    You  will get more help here:
    https://community.atmel.com/communities
    which links to
    https://www.avrfreaks.net/
     
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    LS_IPECO
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    Re: AT90CAN128 is the AGND pin electrically separate from GND? 2018/10/19 01:41:41 (permalink)
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    Thanks Rodims for your thorough answer.
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    MBedder
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    Re: AT90CAN128 is the AGND pin electrically separate from GND? 2018/10/19 04:57:57 (permalink)
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    LS_IPECOAre these three pins connected on the die? I'm looking at a circuit design which assumes PIN63 is separate, the PCB uses a dedicated ground return for this pin and decoupling components for AVCC and AREF.
    See Figure 21-9 on p.282. And bear in mind that GND and AGND are always interconnected on chip in ALL MCUs.


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    rodims
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    Re: AT90CAN128 is the AGND pin electrically separate from GND? 2018/10/19 11:25:21 (permalink)
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    MBedderSee Figure 21-9 on p.282. And bear in mind that GND and AGND are always interconnected on chip in ALL MCUs.

    Upps, so better ignore my assumption and trust MBedders experience. After all you did not ask for the confusing labelling, but for the real silicon.
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