Perry i'm confused, maybe the irs21844 is damaged or fake, Testing with 9v as you recomended in post 83, i did not get what i expected,
when i aplied 9 v betwen VB and VS i lost slowly low side audio signal in gates, and in high side i expected to see 40hz audio signal.
instead of that signal, the dc voltage goes from 0v to -67 volts dc betwen gate and source negative of meter in source (the -67 volts dc remains if 9v is present in pin13), between gate and drain with no 9v between pin 11 and 13 of 21844 i got -86 volts negative in source, when i aplied 9 volts in pin 13 and negative in pin 11 the voltage between source and drain increases to -159 volts negative of meter in source and positive in gate.
when i aplied 9 v betwen VB and VS i lost slowly low side audio signal in gates, and in high side i expected to see 40hz audio signal.
instead of that signal, the dc voltage goes from 0v to -67 volts dc betwen gate and source negative of meter in source (the -67 volts dc remains if 9v is present in pin13), between gate and drain with no 9v between pin 11 and 13 of 21844 i got -86 volts negative in source, when i aplied 9 volts in pin 13 and negative in pin 11 the voltage between source and drain increases to -159 volts negative of meter in source and positive in gate.
Install a 10k resistor between pins 1 and 2 of the TL072 on the output driver board. Does that make a difference?
Is the 9v battery voltage being dragged down (measured across the battery)?
Is the 9v battery voltage being dragged down (measured across the battery)?
i corrected the conection and i got first picture in high side gate and ground
second picture is from low side ths time i do not loose this signal
what do you think?
i tried to start the amp with 8 amps 12 volts (one output mosfet per rail) and the amp can not start tries to start but is demanding more tan 8 amps because the voltage drops to 6v with no output fets the amp draws 3.3 amps , i do not know if i can feed with more amps for the starting process ( the amp with no output fets draws 5.6 amps peak then stabilizes to 3.3 amps) maybe a short in the amp is consuming so much current or the amp need more amps only to start
second picture is from low side ths time i do not loose this signal
what do you think?
i tried to start the amp with 8 amps 12 volts (one output mosfet per rail) and the amp can not start tries to start but is demanding more tan 8 amps because the voltage drops to 6v with no output fets the amp draws 3.3 amps , i do not know if i can feed with more amps for the starting process ( the amp with no output fets draws 5.6 amps peak then stabilizes to 3.3 amps) maybe a short in the amp is consuming so much current or the amp need more amps only to start
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With NO output FETs in the circuit, check the high-side with the scope probe ground clip on the source leg. Make absolutely sure that the ground clip doesn't contact the drain leg.
the battery voltage is 9.50 volts connected in pin 13 and 11 and 9.54 floating (not conected)
another think i think is loy is the driving signal of the power section, im powering the amp with 11.98 volts
i have low driving voltage i think
measured with the fluke are 3.129 volts dc between gate and drain and 3.131 between gate and ground
in the scope i got 4.736 vrms in all gates seems a bit low..
another think i think is loy is the driving signal of the power section, im powering the amp with 11.98 volts
i have low driving voltage i think
measured with the fluke are 3.129 volts dc between gate and drain and 3.131 between gate and ground
in the scope i got 4.736 vrms in all gates seems a bit low..
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Perry the Last image is from the drive of the power section i apologize, i put that picture because the drive voltage seems low to me.
But if low drive voltage in PS is a problem meybe it has nothing in relatión to the audio section problem.
The drive of the audio sección has not chances.
But if low drive voltage in PS is a problem meybe it has nothing in relatión to the audio section problem.
The drive of the audio sección has not chances.
May be, my power source is only 12 volts, for the moment i Will focus in the audio drive section, thank you.
I commented this because i think a remote posibility,that the drive of power section was affecting, but if you are not seeing mayor problem, then i have not to worrie about it
I measured 15 and -15 volts in op amps and are fine 15.23 and -14.92 volts
I commented this because i think a remote posibility,that the drive of power section was affecting, but if you are not seeing mayor problem, then i have not to worrie about it
I measured 15 and -15 volts in op amps and are fine 15.23 and -14.92 volts
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I checked more than two times, and the same signal is present.
But i detected that the signal do not changed when i conected 9 volts between VB and VS, from when there is no 9 volt between this pins.
So i do now if i can do what yo suggested in post 103 to see if the drive signal apears
But i detected that the signal do not changed when i conected 9 volts between VB and VS, from when there is no 9 volt between this pins.
So i do now if i can do what yo suggested in post 103 to see if the drive signal apears
When you checked the drive signal. did you do so on the gate pad of the FETs and also on the high-side output pin of the 21844 driver IC?
Are you connecting the battery to the 21844 that you're trying to check the signal on?
Are you connecting the battery to the 21844 that you're trying to check the signal on?
Yes the pin 12 is HO and it has 0 ohm to the pin i show in the picture (green) the next pin(red) has the low drive output and i can see Low side drive prefectos but i do not foun the high sid drive.
There is only one 21844 The battery is conected ti pin 11 and 13 i attached some photos the point where i connected is zero ohm to pin 11 and positive to pin 13
I starting to think there is something wrong with te IC 21844
There is only one 21844 The battery is conected ti pin 11 and 13 i attached some photos the point where i connected is zero ohm to pin 11 and positive to pin 13
I starting to think there is something wrong with te IC 21844
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Are you 100% sure that there are no damaged vias where the driver board is soldered into the main board?
Do you read 9v across CL1 when you have the 9v battery connected?
What do you mean that you didn't find the high-side drive? You posted photos of it. IT wasn't good but it was present.
Do you read 9v across CL1 when you have the 9v battery connected?
What do you mean that you didn't find the high-side drive? You posted photos of it. IT wasn't good but it was present.