Patent ID: 7295900

Claim:
A load drive apparatus comprising: a driver unit including: a control section modulating, in accordance with a PWM signal, a drive signal to be applied to a load apparatus between a high level and a low level; a short circuit detecting section detecting, on the basis of a signal level of said PWM signal and a signal level of said modulated drive signal, short circuit on a path through which said modulated drive signal is applied to said load apparatus; and a notification section making, on the basis of detection result of said short circuit detecting section, notification whose content represents presence or absence of short circuit on said path; and a control unit generating said PWM signal on the basis of a control program stored therein; wherein said control unit includes a first function of fixing a duty ratio of said PWM signal at one of 0% and 100% when content of said notification made by said notification section represents presence of short circuit on said path, and a second function of determining to which of a high-level side and a low-level side said path is short-circuited on the basis of content of notification made by said notification section after a duty ratio of said PWM signal is fixed by said first function.