ATA6834-DK Atmel, ATA6834-DK Datasheet - Page 4

• Manufacturer Part Number: ATA6834-DK
• Description: BOARD BLDC MOTOR CTRL ATA6833/34
• Manufacturer: Atmel
• Type: MOSFET & Power Driverr

Specifications of ATA6834-DK

• Main Purpose: Power Management, Motor Control
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ATA6833 / ATA6834, ATmega32M1
• Primary Attributes: 3-Ph BLDC, IC with FET Driver, LIN Transceiver, Volt Regulator, Watchdog
• Secondary Attributes: LCD with Touch Screen on MCU Controller Board
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3. BLDC Operation
4
BLDC Motor Control Kit with ATA6833/ATA6834
Brushless DC motors are used in a growing number of applications as they offer several
advantages including reduced noise, long life time (no brush erosion), good weight/size to
power ratio. Brushless DC motors can also be used in hazardous operation environments
such as in the vicinity of flammable products.
These types of motors have a little rotor inertia. Coils are attached to the stator. Commutation
is controlled by electronics using position sensors feedback or back electromotive force
measurements.
BLDC motor stator basically includes three coils, which can be replicated to reduce torque rip-
ple. The rotor includes permanent magnets composed of one to multiple pair of poles. This
also affects step size (see Figure 2). Position can be estimated using three hall sensors,
spread around the stator and attached according to the count of the stator pole pairs every
120°.
Figure 3-1.
BLDC motor operation can be simplified by considering only three coils and one pair pole. The
Phase commutation depends on position, in our case, hall sensors value. When motor coils
are supplied, a magnetic field is created and the rotor moves. The most elementary commuta-
tion driving method is an on-off scheme: a coil is either conducting or not. Only two coils are
supplied at the same time, the third is floating. This is referred as trapezoidal commutation or
block commutation.
Figure 3-2.
C
Three-coil BLDC Motor, 1 and 2 Pair Poles
Power Stage
A
N
S
B
H1
L1
H2
L2
H3
L3
C
A
B
C
S
A
N
N
S
B
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