Re: MMIC question
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Yes. The biassing is such that it is designed to be fed via a resistive droppery. Internally biassing uses feedback to define a roughly constant voltage on the supply pin, which in conjunction with the reisstor causes the device to draw teh correct current. If you 'force' the supply pin to a voltage above that it wants, excessive and uncontrolled current draw will result.
Think 'Zener diode' - its a bit like one of those.
MMICs work best at a constant current defined externally, by an active current source. That is te honly realistic way to run them correctly from a supply that isn't regulated. There is no way you can correctly operate a resistively biassed device from a voltage equal to or below the specified value
HOWEVER, some device around do run from a constant voltage, and the data sheet clearly shows how these can be supplied via only a choke
On 7 August 2016 at 08:40, richard@... [ukmicrowaves] <ukmicrowaves@...> wrote: