Since you haven't told us whether this is a series or parallel circuit
of L's, R's and C's,

O.K. here's the combinatrics:

Combo 1:
DC Sine Wave + (R+L in series with C parallel)

Combo 2:
DC Sine Wave + (R+C in series with L parallel)

Combo 3:
DC Sine Wave + (L+C in series with R parallel)

Combo 4:
DC Sine Wave + (R, L, and C all in parallel with each other)

Combo 5:
DC Sine Wave + (R, L and C all in series)



A peak detector will have to work on the range of voltages expected on it's
input.

O.K., so can I correctly infer from your response that a negative peak
detector will yield a value of +5V for a sine wave which varies from
+5V to +15V?