A load driving apparatus is provided, which includes: a DC high voltage generation circuit, configured to selectively receive one of first and second AC input voltages different to each other, and process the received AC input voltage to obtain and provide a DC high voltage, wherein the DC high voltage obtained by processing either the first or second AC input voltages is substantially or approximately the same; a switching circuit, configured to selectively output the DC high voltage or a ground potential in response to two complementary PWM signals, so as to provide an AC signal; a transformer, having a primary side receiving the AC signal from the switching circuit, and a secondary side providing a driving signal to drive a light-emitting load in response to the AC signal; and a control circuit, configured to generate the two complementary PWM signals to control switching of the switching circuit.