DC Load Regulation and AC Ripple
DC Output Load Regulation
To simulate real world and maximum loading conditions, the Enermax TriAthlor 550W PSU was connected to the load testers and supplied with a constant 115 VAC. In this test we are interested in seeing how well a PSU can maintain the various output voltages while operating under different loads.
The ATX12V V2.2 tolerance for voltages states how much each output (rail) is allowed to fluctuate and has tighter tolerances now for the +12V outputs. I have also included a second table of expanded tolerances (±1% to ±6%) for reference.
The following tables list the DC voltage results for the PSU while operating on 115 VAC, 60 Hz.
As you can see, the TriAthlor 550W PSU produced very good load regulation on the three primary outputs across a broad range of loads and all of the outputs were well within the recommended ATX ranges.
AC Ripple and Noise on the DC Outputs
The amount of AC ripple and noise present on the DC outputs was checked using a digital oscilloscope. This AC component may be present in the KHz range where most switching power supplies operate or it may be more prevalent at the 60 Hz line frequency. We adjust the O-scope time base to look for AC ripple at both low and high frequencies. The ATX12V V2.2 specification for DC output noise/ripple is defined in the ATX12V Power Supply Design Guide.
Ideally we would like to see no AC ripple (repetitive) or noise (random) on the DC outputs – the cleaner the better! But in reality there will always be some present. I measured the amplitude of the AC signal (in millivolts, peak-to-peak) to see how well the power supply complied with the ATX standard. The following table lists the ripple/noise results during all of the load tests for the main output voltages of interest.
The TriAthlor 550W power supply exhibited very good AC ripple suppression on all of the outputs and stayed well below the recommended values, even at full load.
o nikos pinei iremos to
o nikos pinei iremos to kafedaki tou kapou sto syntagma,
kapoia stigmi vlepei to filo t to giwrgo kai pernaei apo
mprosta tou kai ton fonazei.
-giwrgo ela na se kerasw kafedaki kai na ta poume
-ti einai ola auta ta xartia pou exeis mprosta sou?
-logariasmoi giorgo mou eutixws tous eksoflisa kai to
apolamvanw….
-ti? kerdises to laxeio?
-oxi niko mou alla ekana kati pou mporousa na to kanw
eixe i gynaika mou kapoia kosmimata poume den ta forouse
kai kati skeuh asimenia pou den ta xrisimopoiousame,
ta peira loipon kai phga edw stin koloktroni 9 ston kurio
spiropoulo kai ta poulisa.
mou edwse kala leuta kai etsi eksoflisa olous tous logariasmous
mou kai tora to apolamvanw….
http://www.enexyra-athina.gr/
o nikos pinei iremos to
o nikos pinei iremos to kafedaki tou kapou sto syntagma,
kapoia stigmi vlepei to filo t to giwrgo kai pernaei apo
mprosta tou kai ton fonazei.
-giwrgo ela na se kerasw kafedaki kai na ta poume
-ti einai ola auta ta xartia pou exeis mprosta sou?
-logariasmoi giorgo mou eutixws tous eksoflisa kai to
apolamvanw….
-ti? kerdises to laxeio?
-oxi niko mou alla ekana kati pou mporousa na to kanw
eixe i gynaika mou kapoia kosmimata poume den ta forouse
kai kati skeuh asimenia pou den ta xrisimopoiousame,
ta peira loipon kai phga edw stin koloktroni 9 ston kurio
spiropoulo kai ta poulisa.
mou edwse kala leuta kai etsi eksoflisa olous tous logariasmous
mou kai tora to apolamvanw….
http://www.enexyra-athina.gr/