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ADS5400-SP: 2GSPS measurement by phase shifting

Ryo Akashi
Genius 9450 points
Part Number: ADS5400-SP

Hello experts,

My customer plan to AD conversion with 2GSPS speed. Signal will be continuous with same waveform like below.
They would like to take mesurement in 1st waveform and will take nother measurement in 2nd waveform with shifting 2GSPS like bwlow. After taking 2 measurements, they will mix and get 2GSPS speed measurement.
Is it possibke to do with ADS5400-SP only? Or do we need to add some other modify from external side?


Thanks and best regards,
Ryo Akashi

  • 0
    TI__Mastermind 20335 points

    Hi Ryo,

    The term for what your customer is planning to do is to "interleave" two of the ADS5400-SP parts. This will distribute a common input to both of ADS5400-SP with identical front end circuitry, each running at 1GSPS. The input clock to the second ADS5400-SP must be shifted by 500ps in order to accomplish what the customer is after. The ADS5400-SP is unable to shift by 500ps on its own, however the part does have a course (up to 73ps with 2.4ps resolution) and fine (up to 7.4ps with 116fs resolution) adjustment feature in this part to help ease the requirements of the analog clock delay IC. Unfortunately, we don't sell any analog clock delay which would accomplish this task. Additionally, this part does have an internal gain and DC offset adjustments which can be used to calibrate out any inherent gain and/or DC offset mismatch between the two interleaved devices. Hope this helps!

    Regards, Chase

  • 0 in reply to Chase W
    TI__Genius 9450 points

    Hello Chase-san,

    Thank you for your reply. So, it is difficult to get 2GSPS measurement with 1 ADS5400-SP(undersampling, equivalent time sampling)?
    And we need to use 2 ADS5400-SP and additional component which shift 500ps phase like below. Is it correct? 


    Thanks and best regards,
    Ryo Akashi

  • 0 in reply to Ryo Akashi
    TI__Mastermind 20335 points

    Hello Ryo-san,

    Your understanding is correct. Two of the ADS5400-SP is needed to get 2GSPS measurement using this device.

    Regards, Chase