Sampling trigger device and method thereof

摘要

A pulse-width-modulated (PWM) signal [303] controls a driver signal [304] applied to a load device, such as a lamp [106]. A feedback loop samples the driver signal and software at the device adjusts a pulse width of the PWM signal to ensure that a current level of the driver signal is maintained within specified limits. The feedback loop employs a sampling trigger signal [305] to control sampling of the driver signal. An asserting edge and successive negating edge of the sampling trigger signal are established based on comparison of a counter value to a single programmable time value. Accordingly, the sampling trigger signal will have a fixed pulse width.