MC33033 Motorola, MC33033 Datasheet - Page 13

• Manufacturer Part Number: MC33033
• Description: BRUSHLESS DC MOTOR CONTROLLER
• Manufacturer: Motorola

The addition of the RC filter will eliminate current–limit instability caused
by the leading edge spike on the current waveform. Resistor R S should
be a low inductance type.
Figure 24. Current Waveform Spike Suppression
MOTOROLA ANALOG IC DEVICE DATA
6
5
2
V C = 12 V
0.001
The totem pole output can furnish negative base current for
enhanced transistor turn–off, with the addition of capacitor C.
Figure 28. High Voltage Boost Supply
Figure 26. Bipolar Transistor Drive
1
8
This circuit generates V Boost for Figure 23.
MC1455
18 k
S
R
100 mV
Q
4
100 mV
17
16
15
12
17
16
15
12
7
3
C
C
C
C
V M + 8.0
V M + 4.0
1.0 /200 V
V M + 12
1N5352A
R
Boost Current (mA)
R S
0
–
+
*
V M = 170 V
I B
* = MUR115
Base Charge
Removal
20
*
22
40
t
V Boost
MC33033
60
13
Series gate resistor R g will damp any high frequency oscillations caused
by the MOSFET input capacitance and any series wiring induction in the
gate–source circuit. Diode D is required if the negative current into the
Bottom Drive Outputs exceeds 50 mA.
Figure 27. Current Sensing Power MOSFETs
Virtually lossless current sensing can be achieved with the
implementation of SENSEFET power switches.
Gnd
Figure 29. Differential Input Speed Controller
100 mV
Figure 25. MOSFET Drive Precautions
V
V A
V B
Pin 11
17
16
15
12
R 1
R 3
R 4
R S
+
100 mV
V
R 2
A
19
10
11
7
9
R 3
R 1
17
16
15
12
)
)
G
D = 1N5819
M
R 4
R 2
D
REF
EA
Then :
D
K
D
V
If : SENSEFET = MPT10N10M
D
R 2
R 3
S
Power Ground:
To Input Source Return
R g
SENSEFET
Pin 9
40 k
R g
R g
–
R S = 200
V
PWM
Pin 9
R 4
R 3
[
R
V
S
B
[
@
r
DM(on)
I
0.75 I
pk
, 1/4 W
@
R
)
pk
DS(on)
R
13
S