From Newsgroup: sci.electronics.design

There is certainly no need for a linear audio amplifier any more.

This is -70dB at 3kHz and -80 dB at 2kHz

Switching frequency is between about 400 and 550kHz.

Simulation isn't fast. If you want to try it then after fixing much line wrappage
you will need the files from here in the same folder. https://assets.nexperia.com/documents/spice-model/GANE2R7-100CBA_LTspice.zip

The GaN FETs are not very expensive from Digikey and other components should
be low cost except perhaps a suitable filter inductor.

BF721 seems to be obsolete. Any suggestions for an alternative?

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SYMATTR Value BAS21HY
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SYMBOL GANE2R7-100CBA 2016 992 R0
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TEXT -224 1304 Left 2 !.tran 0 100m 0 1u startup
TEXT -232 1400 Left 2 !.MODEL PBSS5140T PNP IS = 2.642E-13 NF = 0.9198 ISE = 1.298E-14 NE = 1.169 BF = 475 IKF = 0.5722\n+ VAF =
28.49 NR = 0.92 ISC = 3.89E-15 NC = 1.161 BR = 36.73 IKR = 0.2593 VAR = 15.08 RB = 25\n+ IRB = 0.0007 RBM = 0.3 RE = 0.1863 RC =
0.09505 XTB = 2.265 EG = 1.11 XTI = 5.73 CJE = 8.437E-11\n+ VJE = 0.6511 MJE = 0.3358 TF = 8.5E-10 XTF = 3.565 VTF = 2 ITF = 0.8 PTF
= 0 CJC = 3.165E-11\n+ VJC = 0.5326 MJC = 0.4006 XCJC = 1 TR = 1.6E-09 CJS = 0 VJS = 0.75 MJS = 0.333 FC = 0.9597
TEXT -232 1584 Left 2 !.MODEL BF721 PNP(IS=5.35E-16 ISE=9.81E-17 ISC=1.00E-13 XTI=3.00 BF=1.40E2 BR=1.00E-2 IKF=2.41E-2\n+ IKR=1.00
XTB=1.5 VAF=1.49E2 VAR=9.18E1 VJE=3.00E-1 VJC=3.00E-1 RE=1.85E-2 RC=2.22 RB=1.99E1\n+ RBM=2.41E-2 IRB=1.10E-2 CJE=4.20E-11
CJC=1.65E-11 FC=5.00E-1 NF=8.73E-1 NR=9.84E-1 NE=1.03\n+ NC=2.00 MJE=4.13E-1 MJC=7.00E-1 TF=1.11n TR=0 ITF=3.00 VTF=9.99E5
XTF=5.76E2 EG=1.11\n+ VCEO=300 ICRATING=50m MFG=SIEMENS)
TEXT -240 1768 Left 2 !.MODEL BF820 NPN IS=9.109E-15 NF=0.9949 ISE=5.02E-24 NE=2.5 BF=141.1 IKF=0.009124 VAF=22.16 NR=0.9917\n+
ISC=6.582E-12 NC=1.397 BR=11.42 IKR=0.02146 VAR=93 RB=1 IRB=1E-06 RBM=0.5 RE=0.3288 RC=0.5195 XTB=0\n+ EG=1.11 XTI=3 CJE=1.504E-11
VJE=0.7202 MJE=0.3499 TF=1.26E-09 XTF=298.9 VTF=2.447 ITF=0.1815 PTF=0\n+ CJC=3.751E-12 VJC=0.158 MJC=0.2757 XCJC=0.1041 TR=1E-08
CJS=0 VJS=0.75 MJS=0.333 FC=0.895
TEXT -224 1344 Left 2 !.options plotwinsize=0
TEXT -176 -160 Left 2 ;Based on https://www.linkedin.com/pulse/gan-devices-class-d-audio-amplifier-tomasz-j-chumiecki
TEXT -176 -112 Left 2 ;Simulation requires https://assets.nexperia.com/documents/spice-model/GANE2R7-100CBA_LTspice.zip
TEXT -176 -64 Left 2 ;January 2026


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