PCB schematic diagram as shown in figure, the current problem is 9 and 13 output waveform without magnification, also did not up, resistance and capacitance basic hardware aspects changed again, thought that chip out of the problem also replace a, is really don't know where the problem is, for a great god answer

CodePudding user response:

The circuit itself doesn't have zoom function, can adjust the negative feedback circuit resistance of 12 k, can change the voltage of the zoom in and out,

CodePudding user response:

Check whether 5, 9 short circuit, 5, 9 if short circuit would be unity gain

CodePudding user response:

refer to the second floor worldy response:

check whether 5, 9 short circuit, 5, 9 if short circuit would be unity gain

Resistance and capacitance are changed, the multimeter checked there is no short circuit

CodePudding user response:

Measuring the VP in the figure,.vn and chip 1245 four pin, VP and.vn after 35 and 39 resistance voltage drive up, but after 36 and 40 two resistance to 1 and 5 pin voltage is not high

CodePudding user response:

VP and.vn after 35 and 39 resistance voltage have a raise, but after 36 and 40 two resistance to 1 and 5 pin voltage has not been raised
LZ you are measuring? You put your test point (positive and negative points);