Oscilloscope Captures 7/14/18: Picking up switching controller noise from laptop charger

in #oscilloscope7 years ago (edited)

Charger Plugged to Laptop

charger_switch_controller_plugged.jpg

Frequency reads about 98kHz

We can tell that the charger uses 100kHz switching controller to regulate the voltage.
charger_switch_controller_plugged_zoom.jpg

Charger plugged off.

Switching frequency increased to about 102kHz to match lower voltage required.
charger_switch_controller_plugged_off.jpg