Good morning everyone, friends, this time I come to ask you for help, an amplifier of the soundstream brand has arrived again and in my last experience I had with another like it, it went wrong but this time the failure is that I have frequency very low in the output fets of only 16khz, what I have been looking for is how to increase their frequency ?, I have seen them working at 118khz in advance greetings
Attachments
I Take it from the Drain of the outfits and remove it to see if the 117kHz appeared on the PIN 14 of 74HC, but i the not seem
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I think this amp may be self oscillating and may require the outputs be in it to oscillate at the correct frequency. Were the outputs in the circuit when you read 16kHz?
Only half of the outputs will have oscillation on their drains if the amp uses all N-channel FETs.
Pin 14 of the 74hc00 is the power supply pin connected to 5v. It should not have had oscillation on it. Confirm in this amp.
By outfits, did you mean outputs?
Terminal 1 of the driver board is the audio input.
Only half of the outputs will have oscillation on their drains if the amp uses all N-channel FETs.
Pin 14 of the 74hc00 is the power supply pin connected to 5v. It should not have had oscillation on it. Confirm in this amp.
By outfits, did you mean outputs?
Terminal 1 of the driver board is the audio input.
You moved the image from a previous post. Please make a note of such editing when you do that sort of editing.
I don't know, maybe I'm already too confused, sorry and I think I confuse you more. The frequency at which it oscillates now is correct (16khz)? Or should the frequency go higher?
16k is definitely not right.
With all of the outputs in the amp, did you drive a signal into the amp to see if the frequency changed?
Did it produce audio?
Did it draw excessive current when you had a 16kHz rail to rail oscillation on the output transistors and the output filter inductor?
With all of the outputs in the amp, did you drive a signal into the amp to see if the frequency changed?
Did it produce audio?
Did it draw excessive current when you had a 16kHz rail to rail oscillation on the output transistors and the output filter inductor?
Yes, I entered a signal with all the outputs inside and no audio was produced, the current consumption did increase, damaging 2 mosfets
With no outputs, load the output locations with a 0.01uF capacitor. What do the waveforms for the high and low side look like?
The load on the drive circuit is across the gate and source of the FETs. Connect the capacitor across the gate and source pads.
