MC33198D MOTOROLA [Motorola, Inc], MC33198D Datasheet - Page 10

• Manufacturer Part Number: MC33198D
• Description: Automotive High Side TMOS Driver
• Manufacturer: MOTOROLA [Motorola, Inc]

Introduction
circuits designed to control power MOSFET devices in high
side switching applications. A brief comparison of both
devices is presented to help the user select the right device for
the application. For a detailed description of the MC33091A,
please refer to the MC33091A data sheet.
General Comparison
has a stand-by mode activated when ever the Input (pin 7) is
in the low state.
7.0V VCC 24V and - 40 C Ambient Temperature 125 C.
The MC33198D does not have as low a stand-by supply
current feature. It’s circuitry is always powered up, causing
the device to have a higher stand-by current but capable of
faster switching making it more suitable for applications
requiring higher Pulse-Width-Modulation frequencies.
output load voltage status in both Input states. This feature
can be used to monitor the load when the MOSFET is off; for
example, when checking for a short to Supply.
MOSFET Protection Features
MC33091A detects the fault and rapidly turns-off the
MOSFET, thus protecting the external MOSFET and it’s load.
The MC33091A automatically attempts to re-energize the
MOSFET so long as the over current condition exists. The
faulted condition duty cycle is determined by the external
components of the MC33091A and over current conditions.
developed across the MOSFET ; the developed voltage
produces a squared current out of pin 8 proportional to the
voltage. The squared current best images the power
MC33198
The MC33091A and MC33198D are Motorola integrated
Both devices are pin-to-pin compatible. The MC33091A
In this case, the supply current is less than 300 A over
In addition, the MC33198D can sense and report the
In case of a MOSFET over current condition, the
The MC33091A monitors the Drain-to-Source voltage
Freescale Semiconductor, Inc.
For More Information On This Product,
MC33091A AND MC33198 COMPARISON
Go to: www.freescale.com
MOTOROLA
MC33198
dissipation of the MOSFET and gives a most accurately
tracks the power dissipation. The produced squared current
determines the charge present on a parallel resistor capacitor
network. The capacitor voltage is monitored and compared to
internal thresholds to cause turn-off and allow turn-on of the
MOSFET. A shorted load condition will produce a large Drain-
to-Source voltage to be developed across the MOSFET,
causing a large pin 8 current to be produced causing the
resistor capacitor network voltage to rise to the a high value
exceeding the threshold level, causing MC33091A to rapidly
turn-off the external MOSFET and thus protect the MOSFET
from catastrophic failure.
voltage developed across the MOSFET is compared to the
voltage present at pin 2. The voltage at pin 2 is created by the
internal reference current and the resistor connected to pin 2
in sensing the Drain voltage. If the Drain-to-Source voltage is
higher than pin 2 voltage, the device will charge the timing
capacitor connected to pin 8 until the capacitor reaches the
internal threshold, then latched off the MOSFET. The
MC33198D will set the fault and keep the MOSFET latched-
off until the input is switched low (off) and turned back on
again.
Fault Status
via pin 6. The MC33091A fault pin is not valid when pin 7 is in
low state, while the MC33198D fault status is valid in both low
and high states of pin 7.
Power Supply
devices have an overvoltage shutdown greater than 20V.
feature which switches off the MOSFET for battery voltages
less than 7V.
The MC33198D feature differs in that the Drain-to-Source
Both devices report the fault status to the microcontroller
Both devices are powered from the battery line. Both
The MC33198D incorporates an undervoltage shutdown
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