M32C8A Datasheet, PDF (211/372 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M32C/80 Series

M32C/8A Group
16. Three-Phase Motor Control Timer Function
Figure 16.14 shows an example of the sawtooth wave modulation operation.
Sawtooth Waveform as a Carrier Wave
Carrier wave
Signal wave
TB2S bit in the
TABSR register
Timer B2
IR bit in the TB2IC register
Set to 0 by an interrupt request acknowledgement or by program
Timer A4 start trigger signal⁽¹⁾
TA4 register
Timer A4 one-shot pulse⁽¹⁾
a₁
a₂
a₃
a₄
a₅
a₆
a₇
a₈
a₁
a₂
a₃
a₄
a₅
a₆
a₇
a₈
Upper arm (U-phase)
output signal⁽¹⁾
Lower arm (U-phase)
output signal⁽¹⁾
DU1 = 1
DU0 = 0
DUB0 = 1 DUB1 = 1
DU0 = 1 DU1 = 1
Rewrite registers IDB0 and IDB1
DUB1 = 1
DUB0 = 0
Values are transferred to the three-phase output shift register from registers IDB0 and IDB1
INV14 bit in
INVC1 register = 0
(Active Low)
U-phase
U-phase
Dead time
INV14 bit in
INVC1 register = 1
(Active High)
U-phase
U-phase
Dead time
NOTE:
1. Internal signals. See Three-Phase Motor Control Timer Function Block Diagram.
The above applies under the following conditions:
- INVC0 register: INV01 bit = 0 (ICTB2 counter is incremented by 1 when timer B2 underflows)
INV02 bit = 1 (Three-phase control timer function used)
INV03 bit = 1 (Three-phase control timer output enabled)
INV06 bit = 1 (Sawtooth wave modulation mode)
- INVC1 register: INV10 bit = 0 (Timer B2 underflow)
INV11 bit = 0 (Timers A11, A21, A41 not used (Three-phase mode 0))
INV15 bit = 0 (Dead time enabled)
INV16 bit = 0 (Falling edge of one-shot pulse of timers A1, A2, and A4)
- ICTB2 register = 01h (Timer B2 interrupt is generated every timer B2 underflow)
- TB2SC register: PWCON bit = 0 (Timer B2 underflow)
The following shows examples to change PWM output levels.
- Default value of the timer: TA4 = a₁ (The TA4 register is changed every time the timer B2 interrupt occurs.)
　　　First time TA4 = a₂, second time TA4 = a₃, third time TA4 = a₄, fourth time = a₅
- Default value of the registers IDB0 and IDB1: DU0 = 0, DUB0 = 1, DU1 = 1, and DUB1 = 1
　　　They are changed to DU0 = 1, DUB0 = 0, DU1 = 1, and DUB1 = 1 at the fourth timer B2 interrupt.
Figure 16.14 Sawtooth Wave Modulation Operation
Rev.1.00 Jul 15, 2007 Page 194 of 352
REJ09B0385-0100