How 3.3nH inductor provides 180deg phase shift?

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Terminator3

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I can't understand where it comes from. There is application note "Tuning the nRF24xx matching network", that says: inductor L1 provides 180deg phase shift at 2.4GHz. I came up with formula:
Code: 
L=50/(2*Pi*2.4)
	L = 3.315727981e0
yes, it is 3.3nH inductor, but why 180deg?
Isn't it 90deg?
I know, it is stupid, but i need help here.

For inductance i learned X=2piFL, current "slower" than voltage 90deg. Adding resistor, shift becomes <90deg
For capacitor X=1/2piFC, current "faster" than voltage 90deg..
 

Read the application note carefully; there is a balun involved with additional L's and C's
 

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C8 and C9 provide a tuned circuit with L1 with the centre tap earthed, this give the 180 degrees phase shift across L1, unfortunately the output is only taken from one end!
Frank
 
A single-pole L or C circuit provides up to 90° phase shift per pole, and to get 180° phase shift, needs at least two poles (LC).
In phase shifter or lumped balun designs very common is to use three poles to provide a 180° phase shift (CLC or LCL).
 
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