Datasheet

As can be seen from the block diagram, the PSC is composed of three modules.
Each of the three PSC modules can be seen as two symmetrical entities. One entity named part A which
generates the output PSCOUTnA and the second one named part B which generates the PSCOUTnB
output.
Each module has its own PSC Input circuitry which manages the corresponding input.
18.5. Functional description
18.5.1. Generating control waveforms
In general, the drive of a 3-phase motor requires generating six PWM signals. The duty cycle of these
signals must be independently controlled to adjust the speed or torque of the motor or to produce the
wanted waveform on the three voltage lines (trapezoidal, sinusoidal, and so on).
In case of cross conduction or overtemperature, having inputs which can immediately disable the
waveform generator’s outputs is desirable.
These considerations are common for many systems which require PWM signals to drive power systems
such as lighting, DC/DC converters, and so on.
18.5.2. Waveform cycles
Each of the three modules has two waveform generators which jointly compose the output signal.
The first part of the waveform is relative to part A or PSCOUTnA output. This waveform corresponds to
sub-cycle A in the following figure.
The second part of the waveform is relative to part B or PSCOUTnB output. This waveform corresponds
to sub-cycle B in the following figure.
The complete waveform is terminated at the end of the sub-cycle B, whereupon any changes to the
settings of the waveform generator registers will be implemented, for the next cycle.
The PSC can be configured in one of two modes (1Ramp Mode or Centered Mode). This configuration
will affect the operation of all the waveform generators.
Figure 18-2. Cycle presentation in One Ramp mode.
Sub-cycle A Sub-cycle B
One P
SC cycle
UPDATE
PSC counte r value
Atmel ATmega16M1/32M1/64M1 [DATASHEET]
Atmel-8209F-ATmega16M1/32M1/64M1_Datasheet_Complete-10/2016
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