i have made a switching-mode power and i want my Atmega16 read if my power work
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in the current scheme,i use the optocoupler pc817 which is connect to the PWM chip(ob2269)’s Vdd.
but, i meet some problems , when the PC817 is connected to the VCC,the PWM chip dont work at all,because its Vin stay at 4.7V (the typical work volt is 19V). if the PC817 is NOT connected, i found the PSU work.
i wonder what caused this problem.
Here ↓ is my scheme pdf and some printscreen pics