Cáp sạc làm giảm Ripple&Noise của củ sạc, cáp càng dài càng giảm!

Summary

The video tests how different USB-C charging cables affect the ripple-and-noise voltage measured from a 45 W charger. The presenter measures the charger at 20 V and 2.25 A, first directly at the charger and then at the far end of each cable.

Measurements

• Directly at the charger: About 421 mV of ripple/noise.
• 50 cm cable: About 251 mV.
• 1 m cables: The tested 5 A cables measure approximately 141–203 mV. Two 3 A cables measure about 151 mV and 159 mV.
• 1.5 m cable: About 132 mV.
• 2 m cable: About 107–108 mV.
• Cable advertised with two E-marker chips: About 141 mV under load. Laying the cable flat instead of bending it makes little difference.

The results vary between cables, including cables of the same length or current rating. Although earlier pulse-generator tests did not show reduced pulse amplitude with some 3 A cables, those cables do reduce the measured ripple/noise in this test.

Takeaway

In this setup, ripple/noise measured at the far end of a cable is much lower than the direct reading at the charger. The longer tested cables tend to show lower readings, but results vary by cable. These measurements use one charger and load, so they should not be treated as a universal ranking of cables.

Test Covered

A hands-on comparison of several 3 A and 5 A cables, including 50 cm, 1 m, 1.5 m, and 2 m examples. Some brand names are uncertain because the source uses auto-generated captions.

Main speaker/source: One presenter from PDH Tech.