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I am building a single phase DC-AC inverter using PWM controller IC LM3524. While testing the PWM chip I find that both the outputs are in phase instead of 180 degree out of phase. Is my understanding about the outputs to be out phase wrong?
If you look at FIGURE 6. on page 7 of the data sheet you will see that the PWM signal drives both output transistors in phase. (It is the output enable signal that drives them in anti phase.) Also if you look at typical applications on paged 8 to 10 you will see in most cases the output transistors are connected in parallel so they must be in phase.
Edit. I have just realised that from figure 6 only one output transistor can be active at a time so the comment about them being shown in parallel is not relevant.
I was thinking when I made my last post, I'm sure I've seen a circuit that switches from sequential drive to parallel drive as a means of reducing the power, thats obviously how its done, probably a sense resistor and a tranny switching the enable line on the ic.
Your suggestion is wonderful. After getting up in the morning I saw your suggestion and tried immediately. I found the trigger set as alternate. When I change it to single, output is perfect. Extremely thankful, spec. Thanks to all others also for their suggestions. Wonderful community!