Itsu,
I did misread the circuit drawing The two 4K are in series. So what you are seeing on pin 2 is VREF. How can the comparator work if this voltage always is VREF?
GL.
Hello All: I agree with Groundloop: The pulse width modulator comparator provides a means for the error amplifiers to adjust the output pulse width from the maximum percent on−time, established by the deadtime control input, down to zero, as the voltage at the feedback pin varies from 0.5 V to 3.5 V. Both error amplifiers have a common mode input range from −0.3 V to (VCC − 2V), and may be used to sense power−supply output voltage and current. The error−amplifier outputs are active high and are ORed together at the noninverting input of the pulse−width modulator comparator . With this configuration, the amplifier that demands minimum output on time, dominates control of the loop.This is from ON-semi spec. sheet TL494. Take care, peace lost_bro
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