Silicon Laboratories C8051F850 BLDC User manual

Rev 0.2 Copyright © 2013 by Silicon Laboratories
C8051F850 BLDC REFERENCE DESIGN QUICK START GUIDE
1 Quick Start
Assemble the MCU board, Powertrain board, motor mount board and motor as shown in the photo below.
Figure 1 BLDC Kit Setup
Connect the motor wiring as shown in the photo –incorrect connection can cause the motor to spin opposite of the
intended direction. Users can select one of two options of powering up the kit. Verify that the jumpers are installed
as shown in the photo below:
Figure 2 MCU Board with default jumper setting

2 Rev. 0.2
External Power Supply Requirements:
DC Voltage: 8 to 12V
DC Current: 6A or more
The user interface behavior is described in the table below:
User interface
Description
SW101
Pushbutton. Controls the direction of rotation of the motor. Pressing this button reverses the
direction of rotation. This button is read by the firmware only when the motor is not running.
SW102
Pushbutton. Starts/stops the motor.
SW301
Pushbutton. Reset button of the C8051F850
R109
Rotary potentiometer. Controls the speed of the motor. Clockwise direction increases the
speed of the motor.
TP308
Header pin. This is the C2D pin of the F850. The motor firmware synchronizes output of this
pin with the electrical cycle of the motor so that the user can monitor the speed of rotation of the
motor. The rotor speed can be calculated by this formula:
Rotor speed (RPM) = (Frequency of TP308 in Hz) x 120 / (Number of poles in motor)
Table 1 BLDC Motor Kit user interface behavior