A packaged device includes a first die, a second die, and specially spaced and positioned sets of package terminals. The first die includes a pulse-width modulator (PWM), a processor, a timer, high-side drivers, low-side drivers, and a fault protection circuit. The second die includes ultra-high voltage high-side drivers. In an ultra-high voltage application, the PWM and external circuitry together form a switching power supply that generates a high voltage. The high voltage powers external high-side transistors. The processor and timer control the ultra-high voltage high-side drivers, that in turn supply drive signals to the external high-side transistors through the package terminals. External low-side transistors are driven directly by low-side drivers of the first die. If the fault protection circuit detects an excessive current, then the fault protection circuit supplies a disable signal to high-side and low-side drivers of both dice. The disable signal is generated without execution of processor instructions.