SH7125_08 Datasheet, PDF (295/774 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family

Section 9 Multi-Function Timer Pulse Unit 2 (MTU2)
4. PWM Output Level Setting
In complementary PWM mode, the PWM pulse output level is set with bits OLSN and OLSP
in timer output control register 1 (TOCR1) or bits OLS1P to OLS3P and OLS1N to OLS3N in
timer output control register 2 (TOCR2).
The output level can be set for each of the three positive phases and three negative phases of 6-
phase output.
Complementary PWM mode should be cleared before setting or changing output levels.
5. Dead Time Setting
In complementary PWM mode, PWM pulses are output with a non-overlapping relationship
between the positive and negative phases. This non-overlap time is called the dead time.
The non-overlap time is set in the timer dead time data register (TDDR). The value set in
TDDR is used as the TCNT_3 counter start value, and creates non-overlap between TCNT_3
and TCNT_4. Complementary PWM mode should be cleared before changing the contents of
TDDR.
6. Dead Time Suppressing
Dead time generation is suppressed by clearing the TDER bit in the timer dead time enable
register (TDER) to 0. TDER can be cleared to 0 only when 0 is written to it after reading
TDER = 1.
TGRA_3 and TGRC_3 should be set to 1/2 PWM carrier cycle + 1 and the timer dead time
data register (TDDR) should be set to 1.
By the above settings, PWM waveforms without dead time can be obtained. Figure 9.41 shows
an example of operation without dead time.
Rev. 4.00 Jul. 25, 2008 Page 275 of 750
REJ09B0243-0400