MC33035 Motorola, MC33035 Datasheet - Page 18

• Manufacturer Part Number: MC33035
• Description: BRUSHLESS DC MOTOR CONTROLLER
• Manufacturer: Motorola

Three Phase Closed Loop Controller
motor speed control. For closed loop motor speed control,
the MC33035 requires an input voltage proportional to the
motor speed. Traditionally, this has been accomplished by
means of a tachometer to generate the motor speed
feedback voltage. Figure 39 shows an application whereby
an MC33039, powered from the 6.25 V reference (Pin 8) of
the MC33035, is used to generate the required feedback
voltage without the need of a costly tachometer. The same
Hall sensor signals used by the MC33035 for rotor position
decoding are utilized by the MC33039. Every positive or
negative going transition of the Hall sensor signals on any of
the sensor lines causes the MC33039 to produce an output
pulse of defined amplitude and time duration, as determined
by the external resistor R
18
The MC33035, by itself, is only capable of open loop
10 k
Speed
Enable
Faster
100 k
5.1 k
F/R
0.01
4.7 k
11
10
12
4
4
1
2
3
5
9
1
2
3
6
7
8
1
and capacitor C
Close Loop
MC33039
MC33035
1.0 M
0.1
Figure 39. Closed Loop Brushless DC Motor Control
18
17
16
15
14
13
24
23
22
21
20
19
1.0 k
1.0 k
8
6
5
7
1
. The output train
Using The MC33035 and MC33039
J
2
J
1
TP
1.0 M
R
750 pF
C
1N5355B
1
1
1
Brake
1.0 k
18 V
MC33035
1N5819
1.1 k
330
Latch On
V
1.1 k
1N4148
M
0.1
Fault
470
470
470
of pulses at Pin 5 of the MC33039 are integrated by the error
amplifier of the MC33035 configured as an integrator to
produce a DC voltage level which is proportional to the
motor speed. This speed proportional voltage establishes
the PWM reference level at Pin 13 of the MC33035 motor
controller and closes the feedback loop. The MC33035
outputs drive a TMOS power MOSFET 3–phase bridge.
High currents can be expected during conditions of start–up,
breaking, and change of direction of the motor.
having 120/240 degrees Hall sensor electrical phasing. The
system can easily be modified to accommodate 60/300
degree Hall sensor electrical phasing by removing the
jumper (J
(18 to 30 V)
The system shown in Figure 39 is designed for a motor
1.1 k
2.2 k
Fault
2
) at Pin 22 of the MC33035.
47
Reset
0.1
0.1
MOTOROLA ANALOG IC DEVICE DATA
1000
100
33
0.05/1.0 W
TP
2
S
Motor
N
N
S