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LTC5548 IF current on Disabled

On my application , i want to increase the signal streng of IF using a Trafo... something like that:

 , On operation  would be periods, when the mixer is deactivated. Is that mean, that during disabled or PowerDown , Is--> could be (3.3V/25Ohm) ~ 130mA?

So in there current control or limitation  during disabled?

i appreciate your comments sugestion or references

  • Hi,

    From the schematic,

    I can see a cap(c1) which will be shorting Vp to ground using transformer.

    Also, I see you are using ADR16-6T transformer which is 1:16 core and wire transformer. Which means you are performing a step down conversion to a very low level(from 50ohms to 50ohms/16) which is completely mismatched.

    All the current is going to the LO amplifier alone and when disabled, no current control is available to start with.



  • Hi Namratha,

    thanks for the reply , but  my question is about the impedance of IF on disabled state... 

    Let say, i use an standar 1:1, 50Ohm ,matched transformer,. On Disabled Vs could be positive? o needs to be 0 when the mixer is disable?.. 

    I appreciate if you go tru this point