This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

ADS5545 single ended input?

Other Parts Discussed in Thread: ADS5545

Hi,

I am using the ADS5545 but I have a single ended source - what is the best way to convert from single ended to differential? Is there a nice app not or a single driver I could use?

  • Calum,

    There are two main ways to do it. One is to use a transformer which can also be used for impedance matching. The second is to use a fully differential amplifier designed for a single-ended input. Which you use is dependent on a lot of factors.

    Transformers are the simplest way with often the best performance. They will not create any distortion or add noise (ideally). The downfall is that they do not pass DC, the gain flatness within their bandwidth varies, and often require two transformers back-to-back to get the differential balancing needed to acheive high performance. We normally use back-to-back transformers on our EVMs to acheive the best performance over a wide range of input frequencies.

    A fully differential amplifier can also be used to convert from single-ended to differential. An amplifier can be setup to pass DC and should have been gain flatness over its bandwidth. The downfall is that an amp is harder to design, it will contribute harmonics of its own, and it will add noise to the system.

    Regards,
    Matt Guibord