Post Go back to editing

LTC6432 as 2x independent amps

Category: Datasheet/Specs
Product Number: LTC6432-15

Hello AD,

1. When using the LTC6432-15 as 2x independent amplifiers: If one of the amplifiers is to be disabled to save power, is an allowable way to achieve this to remove power from the corresponding output feed choke, and if so, would the expected power savings be close to 50%?

2. Is the PSRR of this part vs. frequency perhaps available?

3. Is a channel isolation spec over frequency perhaps available for this part?

Thread Notes

  • Hi  ,

    Good day. LTC6432-15 works as a differential amplifier. If we look at the block diagram, you'll see that the Vcc was connected internally. Hence, it is impossible to disable one of the amplifiers. For the PSRR, there were no available data regarding it. And the channel isolation does not apply to it since the part works as a differential amplifier and is not multichannel. Hope this helps.

    Regards,

    Gilbeys

  • Hello Gilbeys,

    According to:

    ez.analog.com/.../400208

    the LTC6432-15 houses two independent amplifiers, yes, normally used in a differential setup but nevertheless actually independent (indeed, the LTC6433-15 is half of of a LTC6432-15, with only one of the amplifiers operable instead of both).

    I agree that Vcc is connected to both amplifiers internally. However, Vcc also biases the outputs via the output chokes. What happens to the LTC6432 (or LTC6433) power consumption if the part remains powered but one output choke is disconnected? Even if this is slightly non-standard for the LTC6432, is this an allowable mode for these parts according to design?
     

  • Hello Gilbeys,

    Any response on the above, please?

  • 0
    •  Analog Employees 
    •  Super User 
    in reply to bernhardb

    Hi  ,

    Good day. Sorry for the late response. That would create a mismatch between the two amplifiers which could induce distortion at the output. This will probably not optimize the performance of the part across the full bandwidth of operation. 

    Regards,
    Gilbeys