PI3EQX1002B FG EQ TTT S parameter simulation

l  Introduction:

To verify the 4port s parameter model of linear redriver PI3EQX1002B which we provided to the customer, we did AC simulation, transient and step response simulation with 24inch input trace;

Ø  put 24inch input trace

We put 24inch trace on the receiver side of PI3EQX1002B, choose different 4port EQ s parameters to compensate the trace loss and get the eye-diagram at output.

l  Conclusion:

The s parameter is extracted from the linear redriver, it is not bi-directional; only s(4,1)s(4,2) and s(3,1)s(3,2) should be the insertion loss

Port definition:

Port1 = input +

Port2 = input –

Port3 = output+

Port4 = output-

Customer can use below syntax to call the 4port s parameter:

.model smodeleq s n=4 tstonefile='. /eq0fg0.s4p'

spa inp inn outp outn mname=smodeleq

From the transient simulation we can find that the generated s parameter can match well with HSPICE netlist.

l  AC characteristics of Different EQ setting:

Differential insertion loss
SWING=
1200mV
EQ_0 to EQ_3
FG_0 to FG_3 /

EQ_0 corresponds to 10.9dB@5GHz;

EQ_1 corresponds to 6.7dB@5GHz;

EQ_2 corresponds to 8.9dB@5GHz;

EQ_3 corresponds to 13.1dB@5GHz;

FG_0 corresponds to flat gain =-3dB;

FG_1 corresponds to flat gain =-1.5dB;

FG_2 corresponds to flat gain =0dB;

FG_3 corresponds to flat gain =2dB;

l  EQ value table:

4 port s parameter differential insertion loss @ 10meg, 3GHz, 4GHz, 5GHz and 6GHz: (unit:dB)

FG_X EQ_X / 10meg / 3GHz / 4GHz / 5GHz / 6GHz
FG_0 EQ_0 / -2.9855 / 5.2274 / 7.7294 / 10.2227 / 12.6190
FG_0 EQ_1 / -2.9874 / 1.1797 / 3.1164 / 5.2593 / 7.5400
FG_0 EQ_2 / -2.9865 / 3.4354 / 5.7553 / 8.1671 / 10.5913
FG_0 EQ_3 / -2.9846 / 7.2013 / 9.9065 / 12.4256 / 14.6737
FG_1 EQ_0 / -1.5784 / 6.3551 / 8.7878 / 11.2505 / 13.6377
FG_1 EQ_1 / -1.5803 / 2.3073 / 4.1747 / 6.2871 / 8.5595
FG_1 EQ_2 / -1.5794 / 4.5631 / 6.8138 / 9.1950 / 11.6106
FG_1 EQ_3 / -1.5775 / 8.3291 / 10.9651 / 13.4533 / 15.6914
FG_2 EQ_0 / -0.0710 / 7.6846 / 10.1453 / 12.6661 / 15.1098
FG_2 EQ_1 / -0.0730 / 3.6368 / 5.5320 / 7.7024 / 10.0328
FG_2 EQ_2 / -0.0720 / 5.8926 / 8.1712 / 10.6106 / 13.0835
FG_2 EQ_3 / -0.0701 / 9.6586 / 12.3226 / 14.8688 / 17.1619
FG_3 EQ_0 / 1.7540 / 9.3062 / 11.8190 / 14.3958 / 16.8628
FG_3 EQ_1 / 1.7521 / 5.2583 / 7.2055 / 9.4321 / 11.7886
FG_3 EQ_2 / 1.7530 / 7.5142 / 9.8448 / 12.3404 / 14.8383
FG_3 EQ_3 / 1.7549 / 11.2803 / 13.9964 / 16.5982 / 18.9122

l  Transient simulation with netlist and S parameter:

OUTPUT of transient waveform / OUTPUT of eye diagram
FG_2 EQ_0 / /
FG_2 EQ_3 / /

S parameter simulation can match well with Hspice netlist simulation.

l  Step response simulation of 4 port s parameter:

waveform
FG_2 EQ_0 /
FG_2 EQ_3 /

l  characteristic impedance of the s parameter:

The characteristic impedance of the 4port is 47.47ohm at low frequency.