AD9211 Chip Grade

We're using a pair of AD9211 300MSPS ADCS in a design and as a house keeping exercise we are now reading the chip ID and chip grade.

The reading of chip ID agrees with the datasheet (0x6) however the chip grade does not agree.

We read 0x2 whereas the datasheet indicates that 0x0 should be returned for the 300MSPS part.

The ICs have the correct top markings for the 300MSPS and from an ADC perspective are performing correctly.

Attached is a serial port capture of the two reads.

Please can you confirm that this is yet another mistake in the AD9211 datasheet?

  • 0
    •  Analog Employees 
    on Nov 30, 2017 9:21 PM

    Hi, 

    What I have in my notes for the chip grade does differ from the data sheet and would indicate they should be as follows:

    For the AD9211:

    Addr.
    (Hex)

    Parameter Name

    Bit 7
    (MSB)

    Bit 6

    Bit 5

    Bit 4

    Bit 3

    Bit 2

    Bit 1

    Bit 0
    (LSB)

    Default
    Value
    (Hex)

    Default Notes/
    Comments

    Chip Configuration Registers

    02

    chip_grade

    0

    0

    0

    Speed grade:

    10 = 300 MSPS
    00 = 250 MSPS
    01 = 200 MSPS

    X

    X

    X

    Read-only

    Child ID used to differentiate graded devices.

    So I would expect that you would read back 0x10 for the 300Msps speed grade for the entire 8 bit register.  Are you interpreting 0x2 to be only for bits 3:4?

    Regards, 

    David 

  • Hi David,

    Thank you, this agrees with my results.

    I’m only interpreting the two bits and 0x10 is what I’m reading.

    Is the data sheet due to be updated, this one seems to be littered with mistakes.

    Kind regards,

    Tom

    Sent from my iPhone