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ad8055 as a voltage follower

Product Number: AD8055

Hi,

I am considering using a high output drive current  OP AMP as a voltage follower. I found that AD8055 meets the current requirement but in its datasheet, there's no unity-gain stable mentioned.

I wondering if AMP without unity-gain stable could be used as a voltage follower.

Thanks in advance.

Top Replies

    •  Analog Employees 
    •  Super User 
    Oct 13, 2023 +1 verified

    Hi  ,

    Good day. Considering the open loop gain response and the phase margin of the op-amp, we can say that the op-amp is stable at a gain of 1 since it has a positive phase margin (this was based…

    •  Analog Employees 
    •  Super User 
    Oct 13, 2023 +1 verified

    Hi  ,

    There are some cases that amplifiers can be used as voltage follower without unity-gain stable, but for AD8055 case, it is unity-gain stable which can be seen in this plot. 

    Hope this information…

Parents
  • Hi  ,

    Good day. Considering the open loop gain response and the phase margin of the op-amp, we can say that the op-amp is stable at a gain of 1 since it has a positive phase margin (this was based on stability criteria).

    Although the close loop gain response shows a little peaking for frequency above 40 MHz which could only affect the linearity of the output, the part is ensured to have gain flatness 0.1 dB to 40 MHz

    Hope this helps.

    Regards,

    Gilbeys

Reply
  • Hi  ,

    Good day. Considering the open loop gain response and the phase margin of the op-amp, we can say that the op-amp is stable at a gain of 1 since it has a positive phase margin (this was based on stability criteria).

    Although the close loop gain response shows a little peaking for frequency above 40 MHz which could only affect the linearity of the output, the part is ensured to have gain flatness 0.1 dB to 40 MHz

    Hope this helps.

    Regards,

    Gilbeys

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