Specifications

PWM Circuits Associated With Compare Units
6-53 Event Manager (EV)
Other Important Features of Dead-Band Units
The dead-band unit is designed to prevent an overlap under any operating sit-
uation between the turn-on period of the upper and lower devices controlled
by the two PWM outputs associated with each compare unit. This includes si-
tuations when the user has loaded a dead-band value greater than that of the
duty cycle, and when the duty cycle is 100% or 0%. As a result, the PWM out-
puts associated with a compare unit do not reset to an inactive state at the end
of a period when dead band is enabled for the compare unit.
6.5.3 Output Logic
The output logic circuit determines the polarity and/or the action that must be
taken on a compare match for outputs PWMx, for x = 1–12. The outputs asso-
ciated with each compare unit can be specified active low, active high, forced
low, or forced high. The polarity and/or the action of the PWM outputs can be
programmed by proper configuration of bits in the ACTR register. The PWM
output pins can all be put in the high-impedance state by any of the following:
- Software clearing the COMCONx[9] and COMCONx[8] bits, respectively
- Hardware pulling PDPINTx low when PDPINTx is unmasked
- The occurrence of any reset event
Active PDPINTx (when enabled) and system reset override the bits in COM-
CONx and ACTRx
Figure 6–21, on page 6-54, shows a block diagram of the output logic circuit
(OLC). The inputs of Output Logic for the compare units are:
- DTPH1, DTPH1_, DTPH2, DTPH2_, DTPH3, and DTPH3_ from the
dead-band unit and compare match signals
- The control bits of ACTRx
- PDPINTx and RESET
The outputs of the Output Logic for the compare units are:
- PWMx, x = 1–6 (for EVA)
- PWMy, y = 7–12 (for EVB)