MC33030DWR2G ON Semiconductor, MC33030DWR2G Datasheet - Page 8

• Manufacturer Part Number: MC33030DWR2G
• Description: IC CTRLR/DRVR DC SERVO 16-SOIC
• Manufacturer: ON Semiconductor
• Type: DC Motor Driverr

Specifications of MC33030DWR2G

• Applications: DC Motor Controller, Servo
• Number Of Outputs: 1
• Current - Output: 1A
• Voltage - Supply: 8 V ~ 36 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Supply Current: 25 mA
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Load: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

DC motors and sense actuator position by voltage feedback.
A typical servo application and representative internal block
diagram are shown in Figure 17. The system operates by
setting a voltage on the reference input of the Window
Detector (Pin 1) which appears on (Pin 2). A DC motor then
drives a position sensor, usually a potentiometer driven by
a gear box, in a corrective fashion so that a voltage
proportional to position is present at Pin 3. The servo motor
will continue to run until the voltage at Pin 3 falls within the
dead zone, which is centered about the reference voltage.
A and B, each containing hysteresis. The reference input,
common to both comparators, is pre−biased at 1/2 V
simple two position servo systems and can easily be
overridden by an external voltage divider. The feedback
voltage present at Pin 3 is connected to the center of two
resistors that are driven by an equal magnitude current
source and sink. This generates an offset voltage at the input
of each comparator which is centered about Pin 3 that can
float virtually from V
lower offset voltages is defined as the window detector input
dead zone range.
provided. It can be used to buffer and/or gain−up the actuator
position voltage which has the effect of narrowing the dead
zone range. A PNP differential input stage is provided so that
the input common−mode voltage range will include ground.
The main design goal of the error amp output stage was to
be able to drive the window detector input. It typically can
source 1.8 mA and sink 250 mA. Special design
considerations must be made if it is to be used for other
applications.
drive and braking with a maximum source, sink, and brake
current of 1.0 A continuous. Maximum package power
dissipation limits must be observed. Refer to Figure 15 for
thermal information. For greater drive current requirements,
a method for buffering that maintains all the system features
is shown in Figure 30.
between motor startup or locked rotor conditions that can
occur when the actuator has reached its travel limit. A
fraction of the Power H−Switch source current is internally
fed into one of the two inverting inputs of the current
comparator, while the non−inverting input is driven by a
programmable current reference. This reference level is
controlled by the resistance value selected for R
be greater than the required motor run−current with its
The MC33030 was designed to drive fractional horsepower
The Window Detector is composed of two comparators,
To increase system flexibility, an on−chip Error Amp is
The Power H−Switch provides a direct means for motor
The Overcurrent Monitor is designed to distinguish
CC
to ground. The sum of the upper and
OPERATING DESCRIPTION
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CC
for
MC33030
8
mechanical load over temperature; refer to Figure 8. During
an overcurrent condition, the comparator will turn off and
allow the current source to charge the delay capacitor, C
When C
overcurrent latch will go high, disabling the drive and brake
functions of the Power H−Switch. The programmable time
delay is determined by the capacitance value−selected for
C
startup current for a predetermined amount of time. If the
rotor is locked, the system will time−out and shutdown. This
feature eliminates the need for servo end−of−travel or limit
switches. Care must be taken so as not to select too large of
a capacitance value for C
an excessively long time−out period can cause the integrated
circuit to overheat and eventually fail. Again, the maximum
package power dissipation limits must be observed. The
overcurrent latch is reset upon powerup or by readjusting
V
zone. This can be achieved by requesting the motor to
reverse direction.
the integrated circuit and motor by disabling the Power
H−Switch functions if V
of normal operation will commence when V
17.4 V.
Drive/Brake Logic section is shown in Figure 18. The
waveforms grouped in [1] show a reference voltage that was
preset, appearing on Pin 2, which corresponds to the desired
actuator position. The true actuator position is represented
by the voltage on Pin 3. The points V
the input voltage thresholds of comparators A and B that
cause a change in their respective output state. They are
defined as follows:
V
V
V
V
V
V
V
|(V
t
DLY
DLY
Pin 2
1
2
3
4
1
2
2
This system allows the Power H−Switch to supply motor
An Overvoltage Monitor circuit provides protection for
A timing diagram that depicts the operation of the
−V
−V
−V
2
= Comparator B turn−off threshold
= Comparator A turn−on threshold
= Comparator A turn−off threshold
= Comparator B turn−on threshold
−V
.
4
3
4
+
as to cause V
Pin2
= Comparator B input hysteresis voltage
= Comparator A input hysteresis voltage
= Window detector input dead zone range
DLY
I
DLY(source)
V
) − (V
ref
charges to a level of 7.5 V, the set input of the
C
Pin2
DLY
Pin 3
− V
+
CC
4
)| = Window detector input voltage
DLY
to enter or pass through the dead
7.5 C
should exceed 18 V. Resumption
5.5 μA
. An overcurrent condition for
DLY
1
+ 1.36 C
through V
CC
DLY
falls below
4
represent
in μF
DLY
.