SH7211_09 Datasheet, PDF (12/26 Pages) Renesas Technology Corp – MTU2 Three-Phase Complementary PWM Output Function

SH7211 Group
MTU2 Three-Phase Complementary
PWM Output Function (Complementary PWM Mode)
2.2.3 Example of Output with User-Defined PWM Duty
Table 3 summarizes single-phase positive phase and antiphase output operation, showing the relationship between
different PWM duty setting values and the resulting positive phase and antiphase output waveforms.
In complementary PWM mode, the output levels are fixed when the value of the compare register (TGRB_3) is H'0000,
with positive phase output in a constant-on state and antiphase output in a constant-off state. The output levels are also
fixed when the value of the compare register (TGRB_3) is equal to or greater than the setting value of the TGRA_3
register, with positive phase output in a constant-off state and antiphase output in a constant-on state. Figures 9 and 10
show examples of positive phase and antiphase output waveforms.
Note that when the PWM duty is changed, the new setting value is not written directly to the compare register. Instead,
it must be written to the buffer register, after which the compare register is updated via the buffer register.
Table 3 Example of PWM Duty Settings and Output Waveforms
Output Waveform*
TGRB_3 Register Value
Positive Phase Output
(TIOC3B Pin)
Antiphase Output
(TIOC3D Pin)
Waveform
Figure
TGRB_3 ≥ TGRA_3
Constant-off state (high)
Constant-on state (low)
Figure 9 (a)
Between TGRA_3 and
TCDR
Constant-off state (high)
Off waveform output (pulse) —
TGRB_3 = TCDR
Constant-off state (high)
Off waveform output (width Figure 9 (b)
of dead time × 2)
Between (TCDR – Td) and On waveform output (pulse) Off waveform output
—
TCDR
TGRB_3 = (TCDR – Td)
On waveform output (width Off waveform output (width Figure 9 (c)
of dead time × 2)
of dead time × 4)
Between (TDDR × 2) and Complementary PWM waveform output
—
(TCDR – Td)
TGRB_3 = (TDDR × 2)
Off waveform output (width On waveform output (width Figure 10 (a)
of dead time × 4)
of dead time × 2)
Between TDDR and (TDDR Off waveform output
× 2)
On waveform output (pulse) —
TGRB_3 = TDDR
On waveform output (width Constant-off state (high)
of dead time × 2)
Figure 10 (b)
Between H'0000 and TDDR Off waveform output (pulse) Constant-off state (high)
—
TGRB_3 = H'0000
Constant-on state (low)
Constant-off state (high)
Figure 10 (c)
Note: * The PWM output active level is set to low. The example is for single-phase (positive phase,
antiphase) complementary PWM output.
REJ06B0891-0100/Rev.1.00
July 2009
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