Converting a circuit with capacitors and inductors to a circuit with Microstrip Lines

[f_t]

Friends,

I want to convert my circuit which has designed by capacitors and inductors to a circuit without any capacitors and inductors. I mean I want to use only microstrip lines. Could you please help me to do that?
I know that after I gain Electrical Lenght (Beta*x) and Z0, I can convert them by LineCalc in ADS to Mlines, but before it, how I should convert capacitors and inductors to Z0 and Electrical Lenght? I know there is an equation for finding amount of short circuit and open circuit lines to find inductance and capacitance, but should I just use it? It does not any change or adding something else?

 

[jiripolivka]

Friends,

I want to convert my circuit which has designed by capacitors and inductors to a circuit without any capacitors and inductors. I mean I want to use only microstrip lines. Could you please help me to do that?
I know that after I gain Electrical Lenght (Beta*x) and Z0, I can convert them by LineCalc in ADS to Mlines, but before it, how I should convert capacitors and inductors to Z0 and Electrical Lenght? I know there is an equation for finding amount of short circuit and open circuit lines to find inductance and capacitance, but should I just use it? It does not any change or adding something else?

View attachment 108294

To understand the conversion please read about the Smith Chart. If you learn to understand it, then you can replace L and C by transmission lines, also by microstrip.

 

[f_t]

To understand the conversion please read about the Smith Chart. If you learn to understand it, then you can replace L and C by transmission lines, also by microstrip.

I have read about it. I want to know that I should replace capacitors and inductors with open/short microstrip line?

 

[FvM]

It's no reasonable approach to replace L and C by transmission line stubs one by one.

You can most likely achieve the purpose of the discrete LC circuit (impedance matching, filtering) by transmission line segments if you know the specification and the transistor S parameters.

 

[f_t]

It's no reasonable approach to replace L and C by transmission line stubs one by one.

You can most likely achieve the purpose of the discrete LC circuit (impedance matching, filtering) by transmission line segments if you know the specification and the transistor S parameters.

Ok, I can design Matchings/Filters by Mlines. Which kind of Milne/Network of Mlines should I use instead of L2 which has 6.8nH inductance and is a kind of root for biasing?

 

[FvM]

For biasing you can use a λ/4 stub replacing L2/C5. And compensate for transistor output impedance by tuning the line length.

 

[f_t]

For biasing you can use a λ/4 stub replacing L2/C5. And compensate for transistor output impedance by tuning the line length.

Ok, but c4 and L2 are needed for the structure of a Class-E power amplifier and I cannot remove them. Besides, because output current is 4 A, how should I calculate minimum width of the lines used in output? As you know if I use a unreasonable value for width of the lines they would face problem like burning, melting or ... . I am using RO4003 as my board.

 

[FvM]

Ok, but c4 and L2 are needed for the structure of a Class-E power amplifier and I cannot remove them.

Class-E amplifiers with transmission line output circuit have been designed before, I think.