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What does outpout current of ADA4870/LTC6300 means? Peak, Peak-to-Peak, RMS ?

Category: Datasheet/Specs

Hi guys

May I ask what does "output current" in datasheet means?

Here is the screen shot of ADA4780 & LT6300

Does it means 1Apeak=2Apeak-to-peak, or 1Apeak-to-peak, or 1Arms = 1.4Apeak=2.8peak-to-peak? AC or DC? I am looking for an high current output amplifier, but most of them don't show what is output current drive in the output characteristics?

Below is the screenshot of ADA4870 datasheet

Below is the screenshot of LT6300datasheet

Top Replies

  • Hello  ,

    Sorry for the delayed response. Output current on most of our data sheets usually pertains to the DC current that a part is capable of producing on its output which also comes from the current drawn from your DC Supply. 

    Regards,
    Paul

  • Hi Paul 

        Thanks for your reply. Since ADA4870 is a high bandwidth amplifier, I think typically it is used for AC signal.

        May I further ask the emprirical rule for guessing the AC output current (such as 10kHz, 20kHz)?  Or it can preciously be simulated by Ltspice (I doubt ADI has a model on it)?

    Best Regards

    Ward

  • Hello  ,

    What do you mean by AC output current? Are you referring to the RMS value of the DC output current?

    Thanks and regards,
    Paul

  • Hi Paul

    I mean I want to use ADA4870/LTC6300 for generating 10kHz/20kHz sinewave (AC), not DC current.

    Best Regards

    ward

  • Hello  ,

    Let me correct something on my previous statement, the Output Current pertains to the level of current on the part's output that comes from the current drawn from the supplies. This output current could be DC or AC depending on whether your input is also DC or AC. If your input is a DC voltage, your output current will also be DC which comes from the current drawn from the supplies. This is also true if your input is an AC voltage (the output current on this case will be AC and this current comes from the supplies also).

    In order to guess what the AC output current is, the following is what I think that you should consider:

    1. Load at the output

    2. Configuration of amplifier (components used for that configuration and their values)

    3. Input AC voltage and its parameters (amplitude, frequency, etc.)

    4. Current limit of supplies

    For example, ADA4870 has a high output current drive of 1 A meaning it is capable of producing 1 A DC or 1 A peak AC output current, but this will still depend on the conditions that I've mentioned above.

    I hope this helps.

    Regards,
    Paul

  • Hi Paul

    I am grateful for your your detailed reply!

    Best Regards

    ward