TiVECO TVPS450 Power Supply Review
Ripple and Noise Tests
Contents
Voltages at the power supply outputs must be as “clean” as possible, with no noise or oscillation (also known as “ripple”). The maximum ripple and noise levels allowed are 120 mV for +12 V and -12 V outputs, and 50 mV for +5 V, +3.3 V and +5VSB outputs. All values are peak-to-peak figures. We consider a power supply as being top-notch if it can produce half or less of the maximum allowed ripple and noise levels.
The TiVECO TVPS450 provided ripple and noise levels below the maximum allowed during all tests, as you can see in the table below.
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 | Test 6 |
| +12VA | 52.2 mV | 56.2 mV | 38.4 mV | 42.2 mV | 41.0 mV | 41.8 mV |
| +12VB | 53.8 mV | 54.4 mV | 40.0 mV | 41.8 mV | 40.8 mV | 41.8 mV |
| +5 V | 33.4 mV | 32.8 mV | 34.6 mV | 35.6 mV | 36.4 mV | 38.8 mV |
| +3.3 V | 15.2 mV | 15.2 mV | 16.6 mV | 17.4 mV | 18.4 mV | 18.2 mV |
| +5VSB | 12.2 mV | 11.6 mV | 12.2 mV | 13.4 mV | 12.3 mV | 13.4 mV |
| -12 V | 82.2 mV | 86.6 mV | 65.2 mV | 72.4 mV | 68.4 mV | 79.4 mV |
| Input | Test 7 | Test 8 | Test 9 | Test 10 | Test 11 |
| +12VA | 43.8 mV | 47.6 mV | 45.4 mV | 45.8 mV | 51.6 mV |
| +12VB | 42.4 mV | 45.4 mV | 44.4 mV | 43.3 mV | 60.4 mV |
| +5 V | 39.4 mV | 39.2 mV | 39.6 mV | 39.4 mV | 43.4 mV |
| +3.3 V | 20.4 mV | 20.4 mV | 21.4 mV | 21.0 mV | 21.4 mV |
| +5VSB | 13.4 mV | 14.4 mV | 13.8 mV | 12.8 mV | 14.4 mV |
| -12 V | 87.4 mV | 95.2 mV | 96.8 mV | 105.8 mV | 116.4 mV |
Below you can see the waveforms of the outputs during test 11.
Figure 16: +12VA input from load tester during test 11 at 309.9 W (51.6 mV)
Figure 17: +12VB input from load tester during test 11 at 309.9 W (60.4 mV)
Figure 18: +5V rail during test 11 at 309.9 W (43.4 mV)
Figure 19: +3.3 V rail during test 11 at 309.9 W (21.4 mV)