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Block diagram – Motorola M68HC08 User Manual

Page 73

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Hardware Design

Low-Voltage Hardware Set Components

DRM028 — Rev 0

Designer Reference Manual

MOTOROLA

Hardware Design

73

The LV BLDC power stage has both a printed circuit board and a power
substrate. The printed circuit board contains MOSFET gate drive
circuits, analog signal conditioning, low-voltage power supplies, and
some of the large passive power components. This board also has a
68HC705JJ7 microcontroller used for board configuration and
identification. All of the power electronics that need to dissipate heat are
mounted on the power substrate. This substrate includes the power
MOSFETs, brake resistors, current-sensing resistors, bus capacitors,
and temperature sensing diodes.

Figure 4-5

shows a block diagram.

Figure 4-6. Block Diagram

4.6.1.1 Electrical Characteristics of the 3-Ph BLDC Low Voltage Power Stage

The electrical characteristics in

Table 4-6

apply to operation at 25

°C with

a 12-Vdc supply voltage.

POWER

INPUT

BIAS

POWER

BRAKE

MOSFET

GATE

PHASE CURRENT

PHASE VOLTAGE

BUS CURRENT

BUS VOLTAGE

MONITOR

ZERO CROSS

BACK-EMF SENSE

BOARD

ID BLOCK

SIGNALS

TO/FROM

CONTROL

BOARD

POWER MODULE

DRIVERS

MOTOR

TO

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Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

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