circuitking
Full Member level 5
Hi This question already being answered here but I want some clarifications.
https://www.edaboard.com/showthread...de-configurations&highlight=stacked+amplifier
Millimeter-Wave Power Amplifiers by Jaco du Preez, Saurabh Sinha
In the figure, if I don't connect the capacitors (Cn) at the gate terminals then it becomes cascode and if I connect capacitors then it is stacked configurations. is that it?
"The bottom device is configured in a common source mode, while the remainder
of the transistors are operated without grounding any particular terminal in a
common-gate-like setup. "
1.If I imagine the small signal model, the gate teminals will definately be grounded because capacitor is short for AC and VGNs are connected to ground. I don't understand what they mean by that.
"The configuration shown in Fig differs from a cascode amplifier where the common-gate transistor is grounded at the center
frequency. In a stacked design, the gate terminal of the common-gate-like device is
connected to some finite impedance and the drain voltages are added in phase in an
ideal situation"
2.They say some finite impedance, does it mean it can be anything not just capacitance (like resistance, inductance or complex).
3.In the FIgure, it is written Ropt, why does it need to be just resistance, it can be anything right? (I was thinking that I would get that Ropt from loadpull and ignore the imaginary part )
https://www.edaboard.com/showthread...de-configurations&highlight=stacked+amplifier
Millimeter-Wave Power Amplifiers by Jaco du Preez, Saurabh Sinha
In the figure, if I don't connect the capacitors (Cn) at the gate terminals then it becomes cascode and if I connect capacitors then it is stacked configurations. is that it?
"The bottom device is configured in a common source mode, while the remainder
of the transistors are operated without grounding any particular terminal in a
common-gate-like setup. "
1.If I imagine the small signal model, the gate teminals will definately be grounded because capacitor is short for AC and VGNs are connected to ground. I don't understand what they mean by that.
"The configuration shown in Fig differs from a cascode amplifier where the common-gate transistor is grounded at the center
frequency. In a stacked design, the gate terminal of the common-gate-like device is
connected to some finite impedance and the drain voltages are added in phase in an
ideal situation"
2.They say some finite impedance, does it mean it can be anything not just capacitance (like resistance, inductance or complex).
3.In the FIgure, it is written Ropt, why does it need to be just resistance, it can be anything right? (I was thinking that I would get that Ropt from loadpull and ignore the imaginary part )
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