SH7261 datasheet(552/1348 Pages) RENESAS

552 / 1348 page

Section 12 Multi-Function Timer Pulse Unit 2 (MTU2)

Rev. 2.00 Sep. 07, 2007 Page 520 of 1312

REJ09B0320-0200

(p)

Example of AC Synchronous Motor (Brushless DC Motor) Drive Waveform Output

In complementary PWM mode, a brushless DC motor can easily be controlled using the timer gate

control register (TGCR). Figures 12.63 to 12.66 show examples of brushless DC motor drive

waveforms created using TGCR.

When output phase switching for a 3-phase brushless DC motor is performed by means of external

signals detected with a Hall element, etc., clear the FB bit in TGCR to 0. In this case, the external

signals indicating the polarity position are input to channel 0 timer input pins TIOC0A, TIOC0B,

and TIOC0C (set with PFC). When an edge is detected at pin TIOC0A, TIOC0B, or TIOC0C, the

output on/off state is switched automatically.

When the FB bit is 1, the output on/off state is switched when the UF, VF, or WF bit in TGCR is

cleared to 0 or set to 1.

The drive waveforms are output from the complementary PWM mode 6-phase output pins. With

this 6-phase output, in the case of on output, it is possible to use complementary PWM mode

output and perform chopping output by setting the N bit or P bit to 1. When the N bit or P bit is 0,

level output is selected.

The 6-phase output active level (on output level) can be set with the OLSN and OLSP bits in the

timer output control register (TOCR) regardless of the setting of the N and P bits.

External input

TIOC0A pin

TIOC0B pin

TIOC0C pin

TIOC3B pin

TIOC3D pin

TIOC4A pin

TIOC4C pin

TIOC4B pin

TIOC4D pin

6-phase output

When BDC = 1, N = 0, P = 0, FB = 0, output active level = high

Figure 12.63 Example of Output Phase Switching by External Input (1)

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