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AD9542 EEPROM

patrickchen@morrihan.com
on Jan 14, 2021

Hello

     Customer pull-up pin “M3” to let AD9545 load from EEPROM at power-up. “M1” connect to AT24C16D SCL and “M2”  connect to SDA.

But customer cannot see I2C transition during power-up. Is there any strap pin need to config?

 

     Another: How to prepare EEPROM content for factory program?

 

BR

Patrick

  • +1
    •  Analog Employees 
    on Jan 14, 2021 1:57 PM 1 month ago

    Hi,

    First, you need to look with the oscilloscope on the SCL and SDA  pins to see the AD9545 sends out a command byte. If it sends it, the AD9545 is trying to download from the EEPROM. Then look to see why the command byte is not liked by the EEPROM because I suppose the EEPROM does not acknowledge the command byte.

    Looking at the AT24C16D data sheet, I see the EEPROM is organized differently from the 24AA16 used on the AD9545 evaluation board. The AT24C16D is organized as 128 pages of 16 bytes each, which is different from the  24AA16 which is organized as 8 blocks of 256 bytes each. 

    The rule is that when one writes the EEPROM, the page or block boundary cannot be crossed. I do not know if this affects you as you could potentially write the EEPROM on a programmer and then populate it on your board. I am quite sure the AD9545 is not able to program this EEPROM with its configuration.

    I do not see the reading being a problem because both EEPROMs are organized per byte.

    Bottom line is first make the AD9545 send the first command byte, then concentrate in getting the EEPROM to ACK it, then see if the AD9545 can download the EEPROM. If this does not function, change the EEPROM with the one from the evaluation board as we know that EEPROM functions.

    Petre