15.4.3.6 Dead Time

The dead-time feature is used to provide a time period where neither complementary outputs are active at the same time. Dead time is used to prevent both output driver devices (switches) in a bridge from conducting at the same time, causing excessive current flow. Since output switch turn-on and turn-off times are non-instantaneous, dead time is set to ensure that only one device is active. Dead time is implemented by holding off the assertion of the Active state. For the PWMxH and PWMxL outputs, this will delay the rising edge, as shown in Figure 15-30.

Dead-time duration is configured using the PGxDT register. The PGxDT register holds a pair of up to 15-bit dead-time values, DTH and DTL, that are applied independently to the PWMxH and PWMxL outputs, respectively. Dead time is typically only used in Complementary Output mode.