ST7FMC1K2TC STMICROELECTRONICS [STMicroelectronics], ST7FMC1K2TC Datasheet - Page 141

• Manufacturer Part Number: ST7FMC1K2TC
• Description: 8-BIT MCU WITH NESTED INTERRUPTS, FLASH, 10-BIT ADC, BRUSHLESS MOTOR CONTROL, FIVE TIMERS, SPI, LINSCI
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

MOTOR CONTROLLER (Cont’d)
Figure 74. Example of Command Sequence for 6-step Mode (typical 3-phase PM BLDC Motor
Control)
Superimposed voltage
(BEMF induced by rotor)
- approx. HV/2 (PWM on)
- approx. 0V (PWM off)
Note: Control & sampling PWM influence is not represented on these simplified chronograms.
Switch
Node
Step
A
B
C
0
1
2
3
4
5
HV
HV/2
0
HV
HV/2
0
HV
HV/2
0
Demagnetization
Σ
Σ
1
1
HV
HV/2
0V
Σ
2
Wait for BEMF = 0
Σ
3
D
Σ
Σ
2
2
4
C
2
Commutation delay
Σ
5
Z
2
Σ
6
Σ
3
Σ
1
Σ
2
Σ
3
Σ
4
T0
T1
A
PWM off pulses
I
4
D
5
I
5
Σ
Z
5
5
I
1
C
T2
T3
4
B
ST7MC1/ST7MC2
HV
I
I
Σ
6
2
t
6
T4
I
T5
3
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C
1