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CHAPTER 7 INVERTER CONTROL FUNCTIONS
User’s Manual U19678EJ1V1UD
422
7.5.6 Operation as 6-phase triangular wave PWM output function
The 6 triangular wave modulation PWM output function uses seven channels in combination to output a 6-phase
triangular wave PWM waveform (with dead time).
The 6-phase triangular wave PWM output function is an extension of the function described in 7.5.5 Operation as
triangular wave PWM output function with dead time.
It outputs 6 triangular wave modulation PWM from slave channel 2, slave channel 3, slave channel 4, slave
channel 5, slave channel 6, and slave channel 7. Slave channel 1 can be operated in any operation mode. (With this
function, the operation mode of slave channel 1 will not be fixed.)
The output pulse period, positive-phase active width, and reverse-phase active width can be calculated by the
following expression.
Pulse period (down/up) = {Set value of TDR00 (master) + 1}
× 2 × Count clock period
positive-phase active width = {{{Set value of TDR00 (master) + 1}
{Set value of TDRp (slave p) }} × 2
{Set value of TDRq (slave q) + 1}}
× Count clock period
reverse-phase active width = {{{Set value of TDR00 (master) + 1}
{Set value of TDRp (slave p) }} × 2 +
{Set value of TDRq (slave q) + 1}}
× Count clock period
Errors will be included in the output waveforms when the dead time function is used.
The output width of a
positive-phase
will be shortened by the amount of dead time, and the output width of a reverse-phase will be
extended by the amount of dead time. The linearity of output transition will be lost in the neighborhood of 0% and
100% outputs due to the errors.
0% output: Set value of TDRp (slave p)
≥ Set value of TDR00 (master) + 1
100% output: Set value of TDRp (slave p) = 0000H
The master channel operates in the interval timer mode and counts the periods.
A carrier period is generated in two periods of the master channel count.
The count operation of the slave channel is controlled by defining the first period of the master channel as a down
status of the slave channel and the second period as an up status of the slave channel.
TO00 of the master channel outputs up and down statuses.
TO00 of the TO0 register must be manipulated while TOE00 of the TOE0 register is 0 and the default level must be
set, because up and down statuses are output.
TO00 of the TO0 register is set to 1 when MD000 of the TMR0 register is 0, and TO00 is set to 0 when MD000 is 1.
By setting the default level, a high level is output from TO00 during a down status and a low level is output during
an up status.
Slave channel 1 is not used as a 6-phase PWM output function.
(To use the modulation output function, slave channel 1 is used as the real-time output trigger generation channel.
For details of the this function, refer to 7.5.15 Operation as complementary modulation output function).)
Dead time is controlled by using slave channels 2, 4, 6 and slave channels 3, 5, 7 in combination. The 6-phase
triangular wave PWM output function uses slave channels 2 and 3, slave channels 4 and 5, and slave channels 6 and
7 in combination. The output operations of TOp and TOq are explained next.