MC33035 Motorola, MC33035 Datasheet - Page 13

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

Control Circuitry Ground (Pin 16) and Current Sense Inverting Input (Pin 15)
must return on separate paths to the Central Input Source Ground.
Virtually lossless current sensing can be achieved with the implementation of
SENSEFET power switches.
Series gate resistor R
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 Bot-
tom Drive Outputs exceeds 50 mA.
16
MOTOROLA ANALOG IC DEVICE DATA
Figure 29. Current Sensing Power MOSFETs
Gnd
Figure 27. MOSFET Drive Precautions
23
100 mV
40 k
100 mV
21
20
19
9
15
g
will dampen any high frequency oscillations caused
Brake Input
R
S
21
20
19
9
15
D = 1N5819
D
D
D
G
M
D
R
R
R
g
g
g
K
Then : V
V
If: SENSEFET = MPT10N10M
Power Ground:
To Input Source Return
S
SENSEFET
Pin 9
R
S
[
= 200 , 1/4 W
Pin 9
R
S
r
@
DM(on)
0.75 I
I
pk
@
pk
R
)
DS(on)
MC33035
R
S
The totem–pole output can furnish negative base current for enhanced tran-
sistor turn–off, with the addition of capacitor C.
V
6
5
2
CC
0.001
= 12 V
1
8
23
This circuit generates V
Figure 30. High Voltage Boost Supply
Figure 28. Bipolar Transistor Drive
MC1555
18 k
S
R
40 k
100 mV
Q
4
Brake Input
21
20
19
9
15
7
3
Boost
* = MUR115
C
C
C
for Figure 25.
1N5352A
V
V
V
1.0/200 V
M
M
M
+ 8.0
+ 4.0
+ 12
0
V
Boost Current (mA)
M
*
= 170 V
20
*
0
–
+
22
I
B
40
Base Charge
Removal
V
Boost
13
60
t