ADS - Rectifier Circuit

[watatayaya]

Dear all,

I am currently working on simulating a half-wave rectifier and single stage voltage multiplier circuit, and I come across some voltage input difference in the harmonic balance simulation.

Basically, all the parameters (input power, frequency, diodes, capacitors, resistors) are set to be the same. However, the voltage input to the circuit that I measured somehow changes automatically and both voltage input are different .

I have included some pictures in this post to illustrate my point. (Attention to Vin @ 1.8GHz)

Half-wave Rectifier:


Single Stage Voltage Multiplier


As shown in the tables, the voltage input of the half-wave rectifier (0.062V) and the single stage multiplier (0.06V) are different. Could it be due to impedance mismatch between the source impedance (Z= 50 ohms)?

Would deeply appreciate if some advice could be given as I'm required to find out the best efficiency with a few rectifier as well.

Thank you.

 

[BradtheRad]

One circuit draws slightly more Amperes than the other, or one circuit shows in the graph of V-vs-A, that it results in slightly more wasted power than the other.

 

[watatayaya]

@BradtheRad alright noted! so there's no need to do any impedance matching in this case?

 

[pancho_hideboo]

As shown in the tables,
the voltage input of the half-wave rectifier (0.062V)
and the single stage multiplier (0.06V) are different.
Could it be due to impedance mismatch between the source impedance (Z= 50 ohms)?

Simply averaged input impedances over one period are different between them.

Ideally, port sees 3nF//1.5kohm in positive half cycle and infinite in negative half cycle for the half-wave rectifier.

On the other hand, port sees 3nF in negative half cycle and 3nF + 3nF//1.5kohm in positive half cycle for the single stage multiplier.

 

[BradtheRad]

so there's no need to do any impedance matching in this case?

Your first circuit is a half-wave power supply. It tends to deliver bursts of current to the smoothing capacitor. This is a power factor error, in a manner of speaking. You can install an inductor inline with the supply, which softens the spikey behavior of the supply. Perhaps both circuits can benefit from such an inductor. This will change impedance seen by the supply, although it is not necessarily impedance matching as we normally think of it.