I have a amp that is protecting on any speaker load, 4, 2, but will not protect on a 1ohm dummy load. input current is low on all speaker loads. typically under 6amps. But on dummy load i can max out my bench supply at 10amps. Input signal is tone at 60hz and scoping the speaker output is always perfect sign wave, no clipping. I first thought that it was overcurrent or DC offset on the power supply. Pos rail is 58v and neg rail is -58. i also bypassed the over current shunts just to see if that was the case, nope. So i tested again to see which pin on the 494 was going high and it was pin 1. So i am open to what circuit is on pin one
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The audio driver board is your generic type 3 board where you jump 2 and 3 on the 21844 for shutdown in Perry's tutorial.
Those are the same boards (power and audio) as the Maxxsonics PZX class D amps if you have dealt with them. They can be picky.
Is that 6 amps at idle?
Is your dummy load wire wound?
Those are the same boards (power and audio) as the Maxxsonics PZX class D amps if you have dealt with them. They can be picky.
Is that 6 amps at idle?
Is your dummy load wire wound?
yes sir. changed woofers. just because of different ohm load. one was dual 4 and the other was dual 2. was thinking that was over current so we went to dual 4 which was 2 ohm final.
The over-current protection threshold is typically set by a low value resistor (possibly R5). It's generally in series with a 10k resistor (maybe 5.1k here). If the threshold is too low, that could cause it to go into protect early but it should do it on all types of loads. Reactive loads like speakers could cause an irregular type of pulse compared to a dummy load.
The 10k?/270 divider generally drives a 100k resistor and a non-inverting input on the comparator. On that comparator input, there is typically a capacitor that connects to pin 4 of the comparator. That capacitor may be out of tolerance.
The 10k?/270 divider generally drives a 100k resistor and a non-inverting input on the comparator. On that comparator input, there is typically a capacitor that connects to pin 4 of the comparator. That capacitor may be out of tolerance.
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