Motorola M68HC08 Low-Voltage Hardware Set Components, 1 3-Ph AC/BLDC Low Voltage Power Stage

Freescale Semiconductor, Inc.

Freescale Semiconductor, Inc.

Hardware Design

Table 4-5. Characteristics of the BLDC motor

Voltage Constant	Ke	—	8.4	—	V/kRPM
Winding Resistance	Rt	—	2.8	—	Ω
Winding Inductance	L	—	8.6	—	mH
Continuous Current	Ics	—	—	2	A
Peak Current	Ips	—	—	5.9	A
Inertia	Jm	—	0.075	—	kgcm2
Thermal Resistance		—	—	3.6	°C/W

4.6 Low-Voltage Hardware Set Components

4.6.1 3-Ph AC/BLDC Low Voltage Power Stage

Motorola’s embedded motion control series low-voltage (LV) brushless DC (BLDC) power stage is designed to run 3-ph. BLDC and PM Synchronous motors. It operates from a nominal 12-volt motor supply, and delivers up to 30 amps of rms motor current from a dc bus that can deliver peak currents up to 46 amps. In combination with one of Motorola’s embedded motion control series control boards, it provides a software development platform that allows algorithms to be written and tested, without the need to design and build a power stage. It supports a wide variety of algorithms for controlling BLDC motors and PM Synchronous motors.

Input connections are made via 40-pin ribbon cable connector J13. Power connections to the motor are made with fast-on connectors J16, J17, and J18. They are located along the back edge of the board, and are labeled Phase A, Phase B, and Phase C. Power requirements are met with a 12-volt power supply that has a 10- to 16-volt tolerance. Fast-on connectors J19 and J20 are used for the power supply. J19 is labeled +12V and is located on the back edge of the board. J20 is labeled 0V and is located along the front edge. Current measuring circuitry is set up for 50 amps full scale. Both bus and phase leg currents are measured. A cycle by cycle overcurrent trip point is set at 46 amps.

Designer Reference Manual		DRM028 — Rev 0
72	Hardware Design	MOTOROLA
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