Hello guys,
I know that ATX PSU used to power desktop PCs have the following output voltages: 12V, 5V, 3.3V. I know that these voltages are generated only after PSU is powered ON. When PSU/PC is off, there should be only 5V sb (standby) output that powers the mainboard and certain peripherals. When power switch is pressed, pins 16 (green PwrOn) is shorted to pin17 (ground) and all above mentioned voltages are created. When power button is released, psu remain working. What is the voltage on this green PwrOn line?
I know that in laptops, it is 3.3V present on the power switch and this voltage is shorted to ground when power button is pressed.
What happens with ATX switching PSU?
During troubleshoot of one Faulty PSU today, I noticed that if pins 16 and 17are shorted, i.e. psu is jumpstarted it starts working but only until short between 16 and 17 exists. If this short is removed, PSU immediately turns off.
I‘m not sure if this is a correct behavior or not.
Can soneone clarify this start process in more details?
Thank you.
I know that ATX PSU used to power desktop PCs have the following output voltages: 12V, 5V, 3.3V. I know that these voltages are generated only after PSU is powered ON. When PSU/PC is off, there should be only 5V sb (standby) output that powers the mainboard and certain peripherals. When power switch is pressed, pins 16 (green PwrOn) is shorted to pin17 (ground) and all above mentioned voltages are created. When power button is released, psu remain working. What is the voltage on this green PwrOn line?
I know that in laptops, it is 3.3V present on the power switch and this voltage is shorted to ground when power button is pressed.
What happens with ATX switching PSU?
During troubleshoot of one Faulty PSU today, I noticed that if pins 16 and 17are shorted, i.e. psu is jumpstarted it starts working but only until short between 16 and 17 exists. If this short is removed, PSU immediately turns off.
I‘m not sure if this is a correct behavior or not.
Can soneone clarify this start process in more details?
Thank you.
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