R01UH0822EJ0100 Rev.1.00
Page 448 of 1041
Jul 31, 2019
RX13T Group
19. Multi-Function Timer Pulse Unit 3 (MTU3c)
(p) Example of Waveform Output for Driving AC Synchronous Motor (Brushless DC Motor)
In complementary PWM mode when MTU3 and MTU4 are used, a brushless DC motor can easily be controlled using
the TGCRA register.
to
show examples of brushless DC motor driving waveforms created
using TGCRA.
To switch the output phases for a 3-phase brushless DC motor by means of external signals detected with a Hall element,
etc., set the TGCRA.FB bit to 0. In this case, the external signals indicating the magnetic pole position should be input to
timer input pins MTIOC0A, MTIOC0B, and MTIOC0C in MTU0 (make appropriate settings with the MPC and port
mode registers (PMR) of the I/O ports). When an edge is detected at pin MTIOC0A, MTIOC0B, or MTIOC0C, the
output on/off state is switched automatically.
When the TGCRA.FB bit is 1, the output on/off state is switched when the UF, VF, or WF bit in TGCRA is set to 0 or 1.
The driving waveforms are output from the 6-phase PWM output pins for complementary PWM mode.
With this 6-phase output, while the output is turned on, chopping output is available through complementary PWM mode
output function by setting the N bit or P bit in TGCRA to 1. When the N bit or P bit is 0, the level output is selected.
The active level of the 6-phase output (on output level) can be set with the TOCR1A.OLSN and TOCR1A.OLSP bits
regardless of the setting of the N and P bits.
Figure 19.70
Example of Output Phase Switching by External Input (1)
Figure 19.71
Example of Output Phase Switching by External Input (2)
External input
MTIOC0A pin
6-phase output
MTIOC0B pin
MTIOC0C pin
MTIOC3B pin
MTIOC3D pin
MTIOC4A pin
MTIOC4C pin
MTIOC4B pin
MTIOC4D pin
■
When TGCRA.BDC = 1, TGCRA.N = 0, TGCRA.P = 0, TGCRA.FB = 0, and output active
level = high
External input
MTIOC0A pin
6-phase output
MTIOC0B pin
MTIOC0C pin
MTIOC3B pin
MTIOC4A pin
MTIOC4C pin
MTIOC4B pin
MTIOC4D pin
MTIOC3D pin
■
When TGCRA.BDC = 1, TGCRA.N = 1, TGCRA.P = 1, TGCRA.FB = 0, and output active
level = high