Class D 200 Wrms with 2 mosfet cheap

[irvynejay]

yes norazmi i use toner transfer ,flat iron and photo paper,,BTW can you share your non ucd with TLO74+ ir 2110

 

[norazmi]

Yes u can get the schema from scale able ucd, i forgot the pcb file but u can easly draw it back from schema. I can try draw it backk when i back home. Im at vacation now

 

[irvynejay]

d amp

amp now on test 35v-/+
offset idle 33.1mv is this too high i think
please see scope reading on idle and on 100 hrz sine wave
load 4 r
inductor getting hot

 

[irvynejay]

update

replace core with green and 18awg 40 turns
coil is cold
reading of scope is more good than the red core

100 hrz and 250 hrz feed on input
offset decrease at 26.2mv on green core
idle scope reading is good

 

[norazmi]

irvy, inductor getting hot because its not T106-2 and also notice that wrong calculation of inductor also will get high dc offset, suggest to remove the inductor and find ferrite toroid core with air gap 2-3 mm, with same core size you can wind approx 17-18 laps. powered with supply rails +/- 35 should be easy with this amp, your module is correct and u need to find solution for the final part inductor.

 

[norazmi]

the seconfd result is more stable but irvy u still need to measure the inductor correctly

 

[irvynejay]

i cant measure the coil i dont have LCR meter

 

[irvynejay]

norazmi ee ferrite core of psu power supply can be use?

 

[norazmi]

yes can, tell me the size i`ll try measure it for you. usually they are EI33, EI35, EE33, post picture here i`ll try to help you.

 

[norazmi]

btw, im continue old project with ucd style and still 200wrms, but this one more simple and more discrete. Before this we do together with The-Unique from diyaudio. since i`ve got it low thd with LT Spice, will post it later, btw we need to solve your problem first.

 

[irvynejay]

ok ill post some ee core i have to find it ..here are some update change voltage to 50vdc inductor green one with #18 wire 50 turn scope reading good Luke warm on coil irf heat at high gain/volume offset idle reduce at 20mv

 

[norazmi]

ok, i think the core material u have is T106-52 Iron Powder, and with 50 turn u will have approx 82.5 uh and if u lower the turn to get 30uh will be 18 laps i think core will produce heat same as yellow core from psu. u can try with 23 turns will be 50uh. , i think thats why mosfet heat, what about bd139 and bd140? heat? . those bds transistor will produce more than 0.5w if rail supply > +/- 50 (100vdc). measure ac voltage peak high when u play loud post it here.

 

[norazmi]

some result with new project seems to be good.

Circuit: * D:\dx-amp\new D\d-amp projects\cheapd-sim-clipping-lf3\18_cheap-d-v1b-530-393.asc

Early termination of direct N-R iteration.
Direct Newton iteration failed to find .op point. (Use ".option noopiter" to skip.)
Starting Gmin stepping
Gmin = 10
Gmin = 1.07374
Gmin = 0.115292
Gmin = 0.0123794
Gmin = 0.00132923
Gmin = 0.000142725
Gmin = 1.5325e-005
Gmin = 1.6455e-006
Gmin = 1.76685e-007
Gmin = 1.89714e-008
Gmin = 2.03704e-009
vernier = 0.5
Gmin = 3.41758e-010
vernier = 0.25
vernier = 0.125
vernier = 0.0625
vernier = 0.03125
vernier = 0.015625
vernier = 0.0078125
vernier = 0.00390625
Gmin = 2.70031e-010
vernier = 0.00195313
vernier = 0.000976563
vernier = 0.000488281
Gmin = 0
Gmin stepping succeeded in finding the operating point.

Fourier components of V(out)
DC component:-0.29218

Harmonic Frequency Fourier Normalized Phase Normalized
Number [Hz] Component Component [degree] Phase [deg]
1 1.000e+02 3.388e+01 1.000e+00 0.60° 0.00°
2 2.000e+02 5.541e-02 1.635e-03 -91.18° -91.78°
3 3.000e+02 7.362e-02 2.173e-03 -177.99° -178.59°
4 4.000e+02 8.514e-03 2.513e-04 -100.78° -101.38°
5 5.000e+02 2.872e-03 8.477e-05 168.56° 167.96°
6 6.000e+02 4.751e-03 1.402e-04 -101.17° -101.77°
7 7.000e+02 1.154e-02 3.406e-04 -177.47° -178.07°
8 8.000e+02 3.850e-03 1.136e-04 -97.05° -97.66°
9 9.000e+02 6.184e-03 1.825e-04 -174.88° -175.48°
Total Harmonic Distortion: 0.276519%



Date: Sun Feb 12 19:37:22 2012
Total elapsed time: 317.338 seconds.

tnom = 27
temp = 27
method = modified trap
totiter = 7239066
traniter = 7237374
tranpoints = 1674737
accept = 1190616
rejected = 484121
matrix size = 82
fillins = 235
solver = Normal
Matrix Compiler1: 21.3 KB object code size 8.6/5.7/[2.2]
Matrix Compiler2: off [2.7]/2.9/13.0

 

[norazmi]

Vout, Lout, Rload, with 4 ohm, 100 hz with v input amplitude 3.0vrms, supply rails +/- 45.

 

[norazmi]

max output voltage 35 vac with 8 amp lol R#:

 

[irvynejay]

bd140 and 139 is not too hot i can touch it ,,do you mean ill reduce turn in to 23 of the green core or red core same size of wire?
green core reduce to 23 turns is very hot,,scope reading ok but hot irf warm
red core with23 turns is also hot and has bad reading on scope

 

[norazmi]

i mean current core above u mention, have blue and green color. that one.

 

[norazmi]

reduce it to 23 turn@lap will be approx 50 uh, currently u have 50 turn@lap, means 82.5 uh. too much inductance.

 

[irvynejay]

i reduce tuns to 23 #18 green/blue core its very hot and irf is warm scope reading is good but coil is very hot on idle
offset is 24mv

 

[norazmi]

hmmm, need to find ferrite core... , ferrite toroid or ferrite e core which one u have should be ok.