AN2841 Freescale Semiconductor / Motorola, AN2841 Datasheet - Page 3

• Manufacturer Part Number: AN2841
• Description: Using the Hall Decoder (HD) eTPU Function
• Manufacturer: Freescale Semiconductor / Motorola

The HD function is capable of performing commutations to PWMC phases. A detailed description of
commutation is in
3.1
The HD function has been designed to provide as much flexibility as possible in processing the Hall sensor
signals and driving the commutations. This flexibility may allow the HD function to meet the needs of
unusual drive schemes, for example, when used in driving an SR motor. However, since the primary
purpose of the HD function is to drive BLDC motors in a conventional manner, there are several
pre-defined configurations. The Hall sensor positions on stator and generated Hall sensor signals of the
pre-defined configurations are illustrated in
covers the number of phases, internal masks for setting the direction, and other settings.
Freescale Semiconductor
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Revolution Period - This parameter determines the TCR time of the last revolution. The
parameter value is updated each time the sector is changed. The Revolution Period is measured
from the last edge of similar type (low-high / high-low), on the same channel, to the current edge.
Sector Period - This parameter determines the TCR time between the last two changes of the
Sector. The parameter value is updated each time the sector is changed. The Sector Period is
measured from the last edge to the current edge; see
Last Edge Time - This parameter stores the TCR time of the last incoming edge.
Revolution Periods
Example Configurations
Hall Sensor Signals
Sector Periods
Section 3.2,
Figure 3. Measuring Revolution Period and Sector Period
Using the Hall Decoder (HD) eTPU Function, Rev. 0
“Commutation.”
Figure 4
through 9. Each of the pre-defined configuration
Figure
3.
Function Description
3