Diode Does not Passing Voltage while Simulating Full Wave Rectifier in Advanced Design System (ADS)

Edvan

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Hi everyone. I am new on ADS so i'm still trying to learn but now having some problems with simulating the full wave rectifier circuit on the first image. The diode does not pass the voltage through.



I tried to obtain something like this:




Where am i doing wrong about it?
 

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Hi,

are you aware that your scope pictures show you want to pass a 1GHz signal through slow recitfier diodes, designed for mains frequency.
Your test frequency is about 16million times higher than mains frequency. This is not a suitable test condition at all.

On the other hand it does not explain the flat line on 2B.
Also: did you notice that there is no suitable Y scale on the picture 2B?

Klaus
 
Because you do an AC simulation that is not convenient for this circuit. AC simulation is a Small Signal Simulation and it linearizes nonlinear elements around operating point and computes small signal responses.
Instead you have to do either Transient OR HB Simulation in order to see Time Domain/Frequency Domain Waveforms.
 
You are also new to realistic component models.
ALL PARTS HAVE RLC VALUES.

What would you expect to happen if the real 1N4004 has about 100 pF near 0V and 15 pF max (10 pF typ) @ -4V during the insulation state?
What would you expect if the pad pitch was 2 cm and were told it was about 5 to 10 nH/cm during the conductor state including traces?

100 pF is almost 1 Ohm at 1GHz
10 nH is a little over 50 Ohms at 1GHz

With only 1k Load and no cap with some ESR, it looks more like a 50 ohm reactance bridge with the diodes bypassed with a 1 Ohm cap.

You will see that silicon diode Rs is inverse with max case power rating and inverse with junction capacitance too when you look closely at datasheets or examine in a spreadsheet and that parasitic inductance is predictable for a known log(length/width) ratio and trace capacitance is a ratio of area to gap for some dielectric on each side.

Consider every schematic as a "logic diagram" and not an analog diagram until you learn the parasitics of all parts. ESR, ESL, Rp, Rs, Cp.

Also there are no ideal voltage sources they all have an Rs and RF prefers a std. 50 Ohms for MPT.
Also no capacitors or batteries are ideal, so learn to include the analog values like ESR in SMPS schematics and Rs for inductors and for 10850 batteries 10kF + 50mohm for a good Li ion cell with some pre-charge voltage like 3.7 but even that neglects the memory effects charged during CV. Like all double-layer electrolytics and other caps to some extent, a certain % of voltage returns after very brief short circuit.

Welcome to the real world.

By the way can you guess the self resonant frequency of the obsolete 1N4004?
Next time you get a spectrum analyzer try a small signal SRF test.
 
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