when i apply function generator with input frequency of 1KHZ it give output of 3KHZ ......why is that so???????????
any feedback would be highly appreciated
any feedback would be highly appreciated
Hi ALL
Any class D amp design "high important side is level shifter" if it is not good your amp will generate noise,sparking sound etc...
all schematic shows some mistake ...........
If your design analog side voltage is 5V you should provide level shifter same and IR2110 pin 9 should be 5V. PIN 3 you can change 12V or 15V
Regards
MANOJ
Any class D amp design "high important side is level shifter" if it is not good your amp will generate noise,sparking sound etc...
all schematic shows some mistake ...........
If your design analog side voltage is 5V you should provide level shifter same and IR2110 pin 9 should be 5V. PIN 3 you can change 12V or 15V
Regards
MANOJ
after the 6k8 resistor on the positive side(+5.6V)in series,just cut the copper and place the resistor on it.
If level shifter is not good the amplifier will not work at all..😀,or something will get very hot quick.
What mistake have you found in my schematics
?yes there is much noise on outputs but i dint find any source saying this voltage variations😕
this resistor make's the voltage to drop a few m.volt along with the current that goes to the load (TLO71) and the result's temperature,voltage stabilization.
when i apply function generator with input frequency of 1KHZ it give output of 3KHZ ......why is that so???????????
you could also try ferrite core with 3mm gap. i find that they're more readily available at local electronic supplier then iron toroid. or a good iron toroid with low permeability without needing a gap. the etd core that people are suggesting you could find them in a computer power supply. desolder and remove the all the original winding and cut a gap at the center pole.
when i apply function generator with input frequency of 1KHZ it give output of 3KHZ ......why is that so???????????
Hi CPX,
pls show your schematics
if you are using eagtagle's (thread started one Mr.andrew)schematic
Need the changes
1. use LM311P, supply +5v and -5v
2. level shift circuit,both transistor switching voltage is different(one is very high @18V and another is very low @1.3V) so you should correct the voltage both @2.5V to 3V, check with DSO and correct it(for checking use external frequency @200KHz to get neat waveform) after connect IR2110 pin9 +5V PIN3 +12V and MOSFET
3. filter coil for checking use drum core with 60uH(old monitor horizontal linear adj. coil or power booster side coil, remove some turns use it)
Regards
MANOJ
1.I am using lt1016 at +-6.5 volts and gain 9 .Using a faster comparator has given no increase in performance versus lm311N or distorsion decrease(tested),in fact i had additional parasitic oscilations and a capacitor beetween in- and in+ was needed.
2.Level shifter schematic:
Both logic and driver ir2110 supplies are at 12 volts and this si good because it helps with undervoltage lockout modifications that i made.I have simetric signals in level shifter(simulated and measured with max 2 volts difference)
My problem still remains EMI interference(manifested by audio signal noises modulated by sw fresquency difference between channels).
2.Level shifter schematic:
An externally hosted image should be here but it was not working when we last tested it.
Both logic and driver ir2110 supplies are at 12 volts and this si good because it helps with undervoltage lockout modifications that i made.I have simetric signals in level shifter(simulated and measured with max 2 volts difference)
My problem still remains EMI interference(manifested by audio signal noises modulated by sw fresquency difference between channels).
CPX,
without IR2110 (ext. connect freq. @200KHz) check the voltage both (H-in L-in).
when you connect IR2110 both input decreases and the out put you can see the 50% duty cycle wave with noise. when you increase the volume the noise increases and sound will distorted.
for calssD Amp you should sync fsw for 2CH design and good MOSFET will reduce EMI
Regards
MANOJ
I can not sync externaly ,all my syncronizing attemps resulted in huge distorsions aproacing maximum modulation🙁.
from last couple of days i'm trying to ask something but hell with this post nobody is replying....everybdy is busy with there own stuff.....tell me if this place is whole piece of *hit
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The answer is that no one tell you what is wrong without tests.Post switching waveforms,signal waveforms,residual waveforms.