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Agenda. Why do we need SPICE models? SLIC Model net list, alias file circuit file (stimulus file) Result Extraction Cal48.exe (COF generation) Tips and Tricks. Why do we need SPICE models?. The SLIC is a non-linear device--reacts differently at different frequency
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Agenda • Why do we need SPICE models? • SLIC Model • net list, alias file • circuit file (stimulus file) • Result Extraction • Cal48.exe (COF generation) • Tips and Tricks
Why do we need SPICE models? • The SLIC is a non-linear device--reacts differently at different frequency • The SLIC interface to the line has non-linear components • The load(phone) may also be non-linear • The line is non-linear • …essentially we want to know how the SLIC reacts with respect to frequency
SLIC Model • SPICE model for the behavior of the SLIC circuit (*.als and *.net) • Net list of external components used with the SLIC (*.als and *.net) • Stimulus file to quantify the behavior of the SLIC and external circuitry (*.cir)
* Schematics Aliases * .ALIASES ... _ HB2(T/R=$N_0025 VBH=$N_0040 CDC=$N_0039 RDC=$N_0038 ROH=$N_0046 RD=$N_0044 + ILIM=$N_0045 PTG=$N_0018 ZT=$N_0005 CH=$N_0029 VRX_M=$N_0022 VTX_M=$N_0017 ) ... VBH($40) VRX ($22) VTX ($17) T/R ($N25) PTG ($18) ZT ($5) CDC ($N39) RDC ($N38) RD ($N44) CH ($N29) ROH ($N46) ILIM ($N45) Alias File (*.als)
V VBH($40) R2RP $AXBX VRX ($22) VTX ($17) CCRX = 470nF T/R ($N25) 60Ohm CCTX = 470nF RLDC 400Ohm CCH PTG ($18) ZT ($5) CDC ($N39) RDC ($N38) RD ($N44) $RLDC RRPTG = 1MOhm RRS + RRS1 = 108.5KOhm CCDC = 4.7uF CH ($N29) ROH ($N46) ILIM ($N45) CCC = 0.47uF 100nF RRDC = 21.KOhm RROH = 38.3KOhm RILIM = 33.2KOhm RRD = 41.2KOhm Net List (*.net) * Schematics Netlist * R_2RP AXBX $N_0025 60 R_RLDC RLDC AXBX 400 C_CRX $N_0022 VRX 470n C_CTX $N_0017 VTX 470n R_RSIM3 0 VTX 1e12 R_RILIM 0 $N_0045 33.2k R_RD 0 $N_0044 41.2k R_ROH 0 $N_0046 38.3k R_RDC 0 $N_0038 21k V_VBH $N_0040 0 -24V C_CDC 0 $N_0039 4.7u C_CCC 0 $N_0038 0.47u C_CH 0 $N_0029 100n E_HB2_E19 $N_0003 $N_0004 $N_0002 0 1 F_HB2_F13 $N_0005 0 VF_HB2_F13 1 H_HB2_HB2_H2 $N_0035 0 VH_HB2_HB2_H2 -125k VH_HB2_HB2_H2 $N_0043 $N_0046 0V R_HB2_R56 $N_0042 0 500k R_RS1 0 $N_0001 108k R_RPTG 0 $N_0018 1Meg R_RS $N_0001 $N_0005 0.00005k VRX VTX
Transmit Path A/D Stimulus Response Real Part Imaginary Part Stimulus File (*.cir) .lib nom.lib .INC "14slac1a.net" .INC "14slac1a.als" *LINECARD SPICE MODEL FOR K11,K21 Vg 1a 0 AC 1 Rg 1a AXBX 600 Vosc Vrx 0 dc 0 .ac lin 40 100 4000 .print ac vr([AXBX],0) vi([AXBX],0) vr([1a,AXBX]) vi([1a,AXBX]) .print ac vr([vtx]) vi([vtx]) $AXBX $VRX Rg $1a 60Ohm Complete SLIC Model Vg V 1V AC Vosc V 0V DC
Give me the results! Circuit File cont. (*.cir) .lib nom.lib .INC "14slac1a.net" .INC "14slac1a.als" Rg 0 AXBX 600 Vosc Vrx 0 dc 0 ac 1.0 .ac lin 40 100 4000 .print ac vr([AXBX],0) vi([AXBX],0) vr([vrx]) vi([vrx]) .print ac vr([vtx]) vi([vtx]) vr([vrx]) vi([vrx]) $AXBX $VRX Rg 600Ohm Complete SLIC Model Vosc V 0V DC 1V AC
Run the Stimulus Model • Run the Model • The PSPICE will output a *.out file with the results
Extract just the data you need • Run Kpara_outfile.exe to extract the results • Kpara_outfile.exe will produce a *.sli file • The *.sli file is what Cal48.exe uses to generate COF
Run Cal48.exe • Calculation->Calculate (menu option) to generate COF • Select the device (e.g. 1068) • Select the *.sli file • Select all eight channels • Select your GIS (Gain for Impedance Scaling)
Tips and Tricks • GIS is used internally as a feed backloop for the dedicated DSP • GIS is adjustable from -63/64 to +63/64 • You must adjust your GIS to get optimal results • If GIS is too high/low you may get too much feedback • Start near 0 and work your way out • < 0 usually produces better results