*MAX4891 TEST CIRCUIT FILE TO MEASURE
*ETH_ON AND LED_ON CAPACITANCE
*TO CALCULATE ETH_ON CAPACITANCE FOLLOW THE STEPS GIVEN BELOW:
*1. PLOT I(VETH) vs. FREQUENCY
*2. MEASURE I(VETH) AT 1MHz
*3. USE THE EQUATION, C(ETH_ON) = I(VETH)@1MHz/(2*3.142*1E6)
*TO CALCULATE LED_ON CAPACITANCE FOLLOW THE STEPS GIVEN BELOW:
*1. PLOT I(VLED) vs. FREQUENCY
*2. MEASURE I(VLED) AT 1MHz
*3. USE THE EQUATION, C(LED_ON) = I(VLED)@1MHz/(2*3.142*1E6)
.INCLUDE MAX4891.FAM
X1 1 2 3 4 5 6 7 8 9 10 
+  11 12 13 14 15 16 17 
+  18 19 20 21 22 23 24
+  25 26 27 28 29 30 31 32 MAX4891
VDD 30 0 3.3
VGND 11 0 0
VETH 26 0 AC 1
ELED 5 33 26 0 1
VLED 33 0 0
VSEL 29 0 3.3
.AC DEC 100 1K 10MEG
.PROBE
.END