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CHAPTER 7 INVERTER CONTROL FUNCTIONS
User’s Manual U19678EJ1V1UD
498
7.5.15 Operation as complementary modulation output function
The 120 degree excitation method is an inverter control method used for 3-phase brushless DC motors. The
complementary modulation output function can be used to realize this method. By using a complementary method,
braking can also be controlled. The complementary modulation output function sets three duty widths for one period
and generates 3-phase triangular wave modulation PWM output with added dead time (TOp and TOq). The
complementary modulation output function uses one period generation channel (channel 0), three duty generation
channels (channels 2, 4, and 6), and three dead time generation channels (channels 3, 5, and 7) (6-phase triangular
wave PWM output function). See 7.5.6 Operation as 6-phase triangular wave PWM output function for details of
the 6-phase triangular wave modulation PWM function.
The output is modulated in accordance with the TROp and TROq values corresponding to the TOp and TOq pins
that generates the PWM. Channel 1 should therefore be set as the real-time output trigger generation channel. See
7.5.11 Operation as linked real-time output function (type 2) for details of real-time output triggers.
Complementary modulation output is generated by using 6-phase triangular wave PWM, the TROp and TROq
outputs, which are generated by the linked real-time function (type 2), manipulation of the TMEp and TMEq bits of
timer modulation output enable register 0 (TME0) and the TOLp and TOLq bits that are select to specify the addition
of dead time.
The master channel operates in the interval timer mode and counts the periods.
TCRn of slave channel 1 operates in event counter mode and generates a real-time output trigger. The number of
INTTM00 outputs of the master channel is thinned and a real-time output trigger is generated.
When using this function, set the thinning of INTTM00 to odd numbers (1, 3, 5, …).
Slave channels 2, 4, 6 operate in up and down count mode, count the duty factor.
Slave channels 3, 5, 7 operate in one-count mode, count the dead time factor.
A 6-phase triangular wave PWM waveform with dead time is output by changing TOp and TOq by the count
operation (INTTMp, INTTMq) of slave channels 2, 4, 6 (duty) and slave channels 3, 5, 7 (dead time).
Furthermore, modulation output can be controlled by manipulating TMEp and TMEq. The PWM and real-time
outputs are modulated and output from the TOp and TOq pins when TMEp and TMEq are “1”. When TMEp and
TMEq are “0”, the real-time output setting value (TROp and TROq) will be output from the TOp and TOq pins.
To modulate the PWM and real-time outputs and output them from the TOp and TOq pins, determine the default
levels of the TOp and TOq pins according to the settings of TOLp and TOLq of slave channels 2 to 7. (The default
levels are at low level when TOLp and TOLq are “0”, and at high level when TOLp and TOLq are “1”.)
With complementary modulation output, a PWM modulation waveform is output by assuming slave channels 2 and
3, 4 and 5, and 6 and 7 operate as pairs. The operation is as follows.
When TROp = 1, TOLp = 0, TROq = 0 and TOLq = 1, respectively, a positive-phase PWM and a reverse-phase
PWM are output from the TOp pin and TOq pin, respectively.
When TROp = 0, TOLp = 1, TROq = 1, and TOLq = 0, respectively, a reverse-phase PWM and a positive-phase
PWM are output from the TOp pin and TOq pin, respectively.
A positive-phase PWM is output from the TOp pin of a channel for which TROp is set to “1”, and a reverse-phase
PWM is output from the TOq pin of a channel that is to be paired with the channel for which TROp is set to “1”.
(Caution and Remark are listed on the next page.)