Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx> Hi Raj and Jan,Most likely Raj is not exactly at resonance. The phase on one side of resonance will be +90 and on the other side will be -90. The switch from one phase to the other can be quite sudden depending on the Q (if the parallel LC is driven with a series resistance). In his case, I think he has a second L in series with the parallel LC circuit and I'm not certain if there is any resistance other than the signal generator's source impedance, so he may in effect have a series RLC circuit (thevenize the L's and drive the C). One would need to compute the transfer function for phase in this case.
Gerry R.
Original poster: Jan Wagner <jwagner@xxxxxxxxx> Hi,At 09:21 PM 9/26/2006, Raj wrote: Dear forum members,Yesterday, I tried to simulating the behavior of a LCLR circuit using PSPice. I connected a LCLR circuit to an AC source (sine wave generator). The analysis type was 'AC sweep'. Using PSpice, I plotted various graphs with Frequency on the x-axis and the following three parameters in Y-axis:1. Current through Parallel Inductor (inductor in tank circuit) 2. Current through Parallel Capacitor (capacitor in tank circuit) 3. Current through Series inductor. My understanding is that at resonance: 1. The current through the tank circuit's L and C will be same.2. The tank circuit's (either through L or C) will be IN PHASE with the input sine wave source.Depends on the schematic, but if you don't see 0deg phase then maybe you have wired it up as a double resonant converter? E.g. the R is in series with the tank circuit?regards, - Jan