I wonder if it is possible to analyse crossed coupled oscillator in attachment with the way Jony130 did here:http://forum.allaboutcircuits.com/showthread.php?p=200183#post200183.
The circuit that Jony did is Astable Multivibrator but I would like to know if can be apply to my circuit.

 

Now I will ask more specific question and hope someone can help.
For example at first both capacitors and inductors are charged.
Why do you know that at a time there is only one transistor is ON?

 

Why do you know that at a time there is only one transistor is ON?

This MOS transistors form a RS flip-flop
http://en.wikipedia.org/wiki/Flip-flop_(electronics)#Flip-flop_types
And if M1 is ON then Vds1 is smaller then Vgs(on)2 for M2 to also be open.

 

This MOS transistors form a RS flip-flop
http://en.wikipedia.org/wiki/Flip-flop_(electronics)#Flip-flop_types
And if M1 is ON then Vds1 is smaller then Vgs(on)2 for M2 to also be open.

Aha, I have never thought about that
How can you know that when M1 is ON Vds1 is very small that is not enough to open M2?
How can you calculate Vds1?

 

We know that because there is a very strong positive feedback in this type of a circuit.
For example if voltage at point Y is increasing the M1 will be "more open".
This means "more" will current flow through Rp1. So there will be more voltage drop across Rp1 resistor. So the Vsd1 voltage will be drop (at point X). And this will reduces M2 current. And voltage at point Y will increase even more. And voltage at point X will be further decreases and so on.

 

Thanks, I see that it is a bit like differential amplifier.
But what happen after that? I can't see that how the circuit oscillate?

 

I see that it is a bit like differential amplifier.

No, this circuit has nothing to do with the differential amplifier.

But what happen after that? I can't see that how the circuit oscillate?

The tank circuit helps.
http://class.ee.iastate.edu/djchen/ee507/VCO.pdf