AN2009 datasheet(14/39 Pages) STMICROELECTRONICS

Part #	AN2009

Description	PWM MANAGEMENT FOR 3-PHASE BLDC MOTOR DRIVES USING THE ST7MC

PDF	39 Pages

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Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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PWM MANAGEMENT FOR 3-PHASE BLDC MOTOR DRIVES USING THE ST7MC

Compare U registers:

The compare U high and low registers are for setting the duty cycle of the PWM signal in

voltage mode.

COMPARE PHASE U PRELOAD REGISTER HIGH (MCPUH)

Read/Write

Reset Value: 0000 0000 (00h)

Bits 7:0 = CPUH[7:0] Most Significant Byte of phase U preload value

COMPARE PHASE U PRELOAD REGISTER LOW (MCPUL)

Read/Write Read/Write (except bits 2:0)

Reset Value: 0000 0000 (00h)

Bits 7:5 = CPUL[7:3] Low bits of phase U preload value.

Bits 2:0 = Reserved.

4.2 PWM MANAGER IN CURRENT MODE CONTROL

4.2.1 Description

Figure 10. Current regulation in current mode control

CPUH7 CPUH6 CPUH5 CPUH4 CPUH3 CPUH2 CPUH1 CPUH0

CPUL7 CPUL6 CPUL5 CPUL4 CPUL3

set

TIMER

clock

ST7MC

Microcontroller

Motor

Voltage

current

reference

clock

step time

T1-T4

T1-T6

VR02139N

- +

12-bit internal timer

PWM output

AN2009 Datasheet(PDF) 14 Page - STMicroelectronics