MOTOROLA MC33198D

Freescale Semiconductor, Inc...
Freescale Semiconductor, Inc.
MOTOROLA
MC33198
SEMICONDUCTOR
HIGH SIDE
TMOS DRIVER
Automotive High Side
TMOS Driver
SILICON MONOLITHIC
INTEGRATED CIRCUIT
The MC33198D is a high side TMOS driver, dedicated for automotive applications. It is used in conjunction with an external power MOSFET for high
side drive applications. The device can drive and protect a large variety of
MOSFET. The device has CMOS compatible input control, charge pump to
drive the MOSFET gate, fault detection circuitry based on programmable
Vds monitoring to detect shorted load. It also includes a programmable timer
function to eliminate undesired switch off due to in rush currents and a status
pin which reports the output status in both on and off MOSFET state.
The device uses few external components and offers an economical solution
to large current high side switch. It also has PWM capability up to 1kHz.
•Designed for Automotive High Side Driver Application
•Works with a Wide Variety of N-Channel Power MOSFETs
•PWM Capability
•On Board Charge Pump Capable of Charging 25nF in less than 1ms
with No External Components Required
•Drive Inductive Load with No External Clamp Circuitry Required
•CMOS Logic Compatible Input Control
•TMOS Over Current and Short Circuit Protection
•Fault Output to Report an Over MOSFET Current Condition
•Output Status Available when MOSFET is On or Off
•Extended Temperature Range from -40°C to 125°C
•Protected Against Automotive Transients with few External
Components
•Over Voltage and Under Voltage Shutdown
PIN ASSIGNMENT
SRC
1
8
TIMER
DRN
2
7
INPUT
GND
3
6
STATUS
GATE
4
5
VCC
ORDERING INFORMATION
Device
Temperature
Range
Package
MC33198D
- 40°C to+125°C
SO8
Block Diagram and Typical Application
VBAT
VCC
DRN
Over
Volt
Detect
Bias
Supply
Ref
Under
Volt
Detect
Charge
Pump
Rdrn
80µA
POWER
TMOS
GATE
100µA
10µA
Power
ON
15V
INPUT
-
+
5V
C1
C2
LOGIC
-
MCU
Vcc
SRC
Rsrc
+
Rpu
10µA
+
STATUS
C3
-
LOAD
GND
TIMER
C timer
 Motorola,Inc 1999
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MC33198
MAXIMUM RATINGS
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Ratings
Symbol
Value
Unit
Power Supply Voltage (Pin 5)
Vcc
- 0,6 to 60
V
TMOS Source Voltage (Pin 1)
Vsrc
- 0,6 to 60
V
Comparator Threshold (Pin 2)
Vdrn
- 0,6 to 60
V
Gate Output Voltage (Pin 4)
Vgate
- 0,6 to 25
V
Input Voltage (Pin 7)
Vin
- 0,6 to 25
V
Status (Pin 6)
Vst
- 0,6 to 10
V
V(ESD)
+/-2000
V
Tstg
-55 to +150
°C
Operating Junction Temperature
Tj
-40 to +150
°C
Thermal Resistance J/A
Rj
145
°C
ELECTRICAL RATINGS
ESD Voltage Capability
THERMAL RATINGS
Storage Temperature
ELECTRICAL CHARACTERISTICS. Tamb from - 40°C to +125°C, Vcc from 7V to 20V, unless otherwise note. Typical values reflect approximate
mean at 25°C, nominal VCC, at time of device characterization.
Parameters
Symbol
Min
Ilsrc
-10
Ithr
54
Typ
Max
Unit
10
µA
102
uA
10
µA
Vcc+15
V
150
15
µA
µA
SRC Pin 1
Leakage Current
DRN Pin 2
Threshold Current
DRN Leakage, Input Off, Vcc Pin Open
81
Ileak
GATE Pin 4
Output On Voltage at 1ms (Charge Pump ON)
Von
Vcc + 7
Turn Off Current
- with NO Over Vds condition and Vout >0.5V
- with Over Vds condition and Vout >0.5V
Ioutn
Ioutw
70
5
Output Off Voltage.
(Charge Pump OFF and Vcc Pin Open)
Voff
Gate Discharge Current. (Vcc Pin Open)
Ioff
Turn On Time
- Cl = 25nF ; 7V < Vcc < 10V ; Vout > Vcc+7
- Cl = 25nF ; 10V < Vcc < 20V ; Vout > Vcc+10
ton
110
10
V
0
0.9
µA
5
ms
1
1
VCC Pin 5
Supply Voltage Range
Vcc
Quiescent Supply Current ; In = 0V
- at Vcc = 7V
- at Vcc = 20V
Iccq
Supply Current ; In = 5V
Icc
1
Over Voltage Threshold
Vo v
22
Under Voltage Threshold
Vur
MC33198
7
20
V
mA
1.8
2.8
4
6
35
mA
28
34
V
6
7
V
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ELECTRICAL CHARACTERISTICS.Tamb from - 40°C to +125°C, Vcc from 7V to 20V, unless otherwise note .Typical values reflect approximate
mean at 25°C, nominal VCC, at time of device characterization.
Parameters
Symbol
Min
Typ
Max
Unit
Vol
0,1
0,4
1.5
V
1.5
V
STATUS Pin 6
Output Voltage @I = 1mA
INPUT Pin 7
Input Low Voltage
Vil
Input High Voltage
Vih
3.5
V
Vhys
0.8
V
Input Pull Down Resistor. Vin >11V
Rin
20
Open Input Voltage
Viop
Input Hysteresis
36
100
kΩ
1
V
TIMER Pin 8
Timer Current
Itime
7
10
14
µA
On Threshold
Vhth
5.2
5.5
5.8
V
Discharge Current @V pin8 = 5V
Idisch
2
5
10
mA
Saturation Voltage @I pin8 = 1mA
Vsat
0,15
0.4
V
DYNAMIC ELECTRICAL CHARACTERISTICS
Parameters
Vcc = 7V
Vcc = 14V
Vcc = 21V
Unit
TYPICAL RISE TIME (t r ) versus Gate External Capacitor Load and Supply Voltage (refer to figure 1)
C = 1nF
15
7
10
µs
C = 3nF
60
25
40
µs
C = 10nF
140
80
90
µs
C = 30nF
730
270
340
µs
TYPICAL FALL TIME (t f) versus Gate External Capacitor Load and Supply Voltage (refer to figure 1)
C = 1nF
150
230
280
µs
C = 3nF
430
800
950
µs
C = 10nF
1200
2300
2750
µs
C = 30nF
4800
8000
9200
µs
Figure1. Timing Measurement Test Schematic
INPUT Pin 7
Vcc
1
2
SRC
DRN
5
VCC
6 STATUS
5V
0V
GATE 4
GATE Pin 4
Typically (V cc + 15V)
C
7 INPUT
TIMER
GND
8
3
90%
10%
tr
MC33198
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Figure2. Supply Current versus Supply
Figure3. Supply Current versus Supply
Voltage. Pin 7 = 0V
Voltage. Pin 7 = 5V
5
Ta = -40°C
4
Ta = 125°C
3
2
Ta = 25°C
1
SUPPLY CURRENT (mA)
SUPPLY CURRENT (mA)
Freescale Semiconductor, Inc.
25
20
15
10
5
0
0
5
10
15
20
25
5
10
Vcc, SUPPLY VOLTAGE (V)
Figure4. Time Current versus Supply
15
20
Vcc, SUPPLY VOLTAGE (V)
25
Figure5. Drain Current versus Supply Voltage
Voltage
Ta = -40°C
10
Ta = 25°C
9
Ta = 125°C
8
DRAIN CURRENT (uA)
TIMER CURRENT (uA)
11
Ta = 25°C
80
Ta = - 40°C
78
76
74
Ta = 125°C
72
5
10
15
20
5
25
10
15
20
25
Vcc, SUPPLY VOLTAGE (V)
Vcc, SUPPLY VOLTAGE (V)
Figure6. Fault Output Voltage versus Current
Figure7. Gate Voltage versus Voltage
40
2
25°C
Ta = 125°C
Vg, GATE VOLTAGE (V)
FAULT OUTPUT VOLTAGE (V)
Freescale Semiconductor, Inc...
MC33198
1.5
1
Ta = 25°C
0.5
Ta = -40°C
35
125°C
-40°C
30
25
20
15
0
MC33198
1
2
3
4
FAULT OUTPUT CURRENT (mA)
5
5
20
10
15
Vcc, SUPPLY VOLTAGE (V)
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Figure8. Gate Voltage versus Gate
Figure9. Gate Voltage versus Gate
Output Current. Ta = 25°C.
Output Current. Ta = 125°C
40
40
VCC = 21V
VCC = 21V
35
GATE VOLTAGE (V)
GATE VOLTAGE (V)
35
30
25
VCC = 14V
20
15
10
VCC = 7V
5
30
VCC = 14V
25
20
VCC = 7V
15
10
5
0
1
2
3
GATE OUTPUT CURRENT (mA)
0
4
Figure11. Gate Voltage versus Vcc
Output Current. Ta = 40°C
and Rg at Ta = 25°C
4
35
VCC = 21V
35
1
2
3
GATE OUTPUT CURRENT (mA)
Figure10. Gate Voltage versus Gate
40
30
30
GATE VOLTAGE(V)
GATE VOLTAGE (V)
Freescale Semiconductor, Inc...
MC33198
25
VCC = 14V
20
15
10
VCC = 7V
25
20
15
No Rg
R g = 68K
R g = 39K
R g = 15K
10
5
5
0
0
MC33198
1
2
3
GATE OUTPUT CURRENT (mA)
4
5
7
9
11
13
15
17
Vcc , SUPPLY VOLTAGE (V)
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MC33198
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Figure 12. Descriptive
Waveform Diagram
< 30V and > 20V
UNDER VOLTAGE THRESHOLD
Vbat
UNDER VOLTAGE THRESHOLD
VCC PIN 5 (V)
0V
5V
IN PIN 7 (V)
0V
110 µA GATE DISCHARGE CURRENT
10µA GATE DISCHARGE CURRENT
10µA DISCHARGE
Vbat + 14V
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MOSFET GATE (V)
0V
< Vbat
PIN 2 VOLTAGE
LOAD VOLTAGE (V)
MOSFET SOURCE (V)
0V
10V
5,5V
TIMER PIN 8 (V)
0V
FAULT PIN 6 (V)
5V
0V
NORMAL SWITCH ON/OFF
MC33198
TEMPORY
OVERLOAD
PERMANENT OVERLOAD
MOSFET OFF
LOAD SHORTED TO VBAT
OVERVOLTAGE CONDITION
UNDERVOLTAGE CONDITION
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Freescale Semiconductor, Inc...
MC33198
FreescaleDEVICE
Semiconductor,
Inc.
DESCRIPTION
Introduction
The MC33198D is a high side TMOS driver, dedicated for
automotive applications. It is used in conjunction with an
external power MOSFET for high side drive applications. The
device can drive and protect a large variety of MOSFET. The
device has CMOS compatible input control, charge pump to
drive the MOSFET gate, fault detection circuitry based on
programmable Vds monitoring to detect shorted load. It also
includes a programmable timer function to eliminate
undesired switch off due to in rush currents and a status pin
which reports the output status in both on and off MOSFET
state. The device uses few external components and offers an
economical solution to large current high side switch. It also
has PWM capability up to 1kHz.
Power Supply
The MC33198D can be supplied from the battery line. It is
designed in a 60V technology, making it able to sustain up to
60V transient pulses. In off state, with pin 7 low, the supply
current is up to 5mA, and in operation, pin 7 high, the current
up to 25mA. The device has an undervoltage detection and
shutdown near 7V. Below this value the MOSFET is turned
off. There is also a 25V overvoltage detection which switches
off the output pin 4 to protect both MOSFET and load when
Vcc is higher than 25V.
Charge Pump
The device incorporates a self running charge pump with
internal capacitor and connected at Gate pin 4. To prevent
oscillation, a serial resistor can be added. The charge pump is
able to charge a 25nF capacitor in less than 1ms. This allows
the MC33198D to have a rapid response time and to drive the
external TMOS gate very quickly, allowing fast switching on of
the load. The device has an internal 14V zener diode between
pin 4 and 1 to clamp the Gate-to-Source voltage and protect
the MOSFET gate oxyde from destruction. See Dynamic
Electrical Characteristics table for details.
Band Gap and Reference Currents
The MC33198D has an internal band gap reference
voltage which generates all the internal thresholds. This band
gap is also used to generate internal reference currents
necessary for proper operation of the device.
These currents are :
Pin 2 : Drain current (typically 80µA).
Pin 4 : High and low gate discharge currents (typically
100µA and 10µA).
Pin 8 : Timer charge current (10µA typical).
All these currents are derivated from the same reference
voltage and internal resistor. Their accuracy and variability is
approximately +-25% over the full temperature and voltage
range. In addition, a passive pull down current of 5µA
maintains the gate of the MOSFET below 0.9V when the
device has no supply, ensuring that the MOSFETremains off.
This passive pulldown current is operating even if device V cc
(pin 5) is not powered up.
MC33198
Input Circuitry
The input of the device is CMOS compatible and can be
directly connected to a microcontroller. The input current is
determined by an internal pull down resistor of typically 36kΩ.
A hysteresis of 0.8 V minimum is present at this input.
Output Status
The device has a status output (pin 6) which has an open
collector structure. This pin is used to report the MOSFET
over load condition or the LOAD status when MOSFET is off.
The device Pin 1 (Source) is compared to a programmable
threshold at Pin 2, in both on and off state of the MOSFET.
This allows the detection of MOSFET over Vds or over load
conditions when MOSFET is on and load short to Vbat
monitoring when MOSFET is in off state. This status pin is
normally connected to a pull-up resistor and to a micro input
and can drive up to 1mA. See below for detailed operation.
Timer
The timer (pin 8) is used in conjunction with an external
capacitor to create a delay between the over load detection
and the shutdown of the MOSFET. In case of over load, the
internal current source pin 8 will charge the capacitor. When
the voltage at pin 8 reaches the 5.5V threshold, the internal
C3 comparator will be triggered and switch off the output to
protect the MOSFET. The fault and the MOSFET turn off
condition are latched and are reset by switching the input off
and on. The delay between over load detection and actual
MOSFET turn off is used to allow temporary over load wich
will prevent the system from switching off during possible inrush current or transients.
MOSFET Protection and Output Voltage Monitoring
The MC33198D has the ability to sense the output
MOSFET source voltage and compare it to a predetermined
threshold. This threshold is programmable using the internal
reference current of 80µA and an external resistor connected
at pin 2. The device can monitor the output load voltage, as
well as protect the MOSFET in case of over load.
The over load detection threshold must be adapted to the
MOSFET itself depending on the load to be driven and the
thermal capability of the MOSFET. In practice, the maximum
acceptable Vds of the MOSFET should be determined and
based upon MOSFET maximum power dissipation.
In addition, the pin 8 capacitor value should be calculated
to allow inrush current.
Source (Pin1) and Drain (Pin2) Functionality
These two pins are used to sense the MOSFET and load
conditions. Pin 2 is connected to the internal pull down current
source of 80µA and to the C2 comparator. An external resistor
connected between pin 2 and Vbat creates a voltage drop
across this resistor. The voltage drop will be the MOSFET
maximum acceptable drain to source voltage and the C2
comparator threshold.
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Pin 1 is connected to the MOSFET source pin. Two
different cases should be considered, MOSFET on or off :
When MOSFET is on and working in normal conditions,
the Vds should be less than the voltage developed at pin 2.
So, the C2 comparator output is low and the status is high. No
current will flow through the pin 8 capacitor.
If the MOSFET encounters an over-load or if the load is shorted to Gnd, the voltage at the source will cross pin 2 voltage
and go below this pin 2 voltage, thereby turning on the C2
comparator. The comparator will pull the status pin 6 low and
will enable the charge of the pin 8 capacitor. When the voltage at the capacitor reaches 5.5V, the C3 comparator will
switch off the MOSFET by disabling the charge pump and
the 110µA current source. The MOSFET gate will be discharged only by the 10µA current source. The MOSFET is
latched off and can be turned back on again by switching
input pin 7 to 0 and back to 1.
When MOSFET is off, we have the same scheme.
In normal condition the load should pull the source voltage
to Gnd, thus C2 comparator output is high and status pin
pulled low. If the load is shorted to V bat for instance, source pin
will be higher that pin 2, C2 output comparator is low and
status pin is high. This is summarized in the following table :
The 100µA source can be disabled. This is the case when
the MOSFET is switched off under fault conditions. The
device will disable the 100µA current source and the
MOSFET gate will be discharged only by a 10µA current. The
time required to switch off the MOSFET will be much longer in
this case and will result in a lower over-voltage at the
MOSFET, especially when the device drives high inductive
loads.
T a b l e 1 • Status Functionality
PWM Operation
Since the MC33198D charge pump can deliver a high
current, the MOSFET gate can be charged fast enough to
allow PWM operations. The maximum PWM frequency is
dependent on the MOSFET itself and mainly its gate to source
capacitor value. Depending on the PWM frequency, the
switching off time can be long, compared to the on-switching
time response. This is due to the 110µA gate discharge
current. To improve this parameter, a resistor can be added in
parallel with the gate of the MOSFET. See figures 13 and 14
below.
Input
Condition
Source
Load
Voltage
C1
Output
Comp
Fault
Pin6
Timer
Pin8
Low
Normal
< Vpin2
High
Low
Low
Low
Short circuit
to V bat
> Vpin 2
Low
High
Charge
by 10µA
source
High
Normal
> Vpin 2
Low
High
Low
High
Short to
Gnd
or Over load
< Vpin2
High
Low
Charge
by 10µA
source
Off State Operation without Vcc Connection
When pin 7 is in low state the MOSFET is off. If V bat is
present, the gate voltage is discharged by the 110µA current
source. In the case of Vbat disconnection, a self sustaining
5µA pull down current source is incorporated in the device to
ensure that the MOSFET gate capacitor is discharged and
tied below 0.9V. In case of Vcc disconnection, input pin 7 has
no effect on gate voltage which is maintained below 0.9V and
in this case, status pin is high. Low leakage current at pin 2
(10µA max) allows operation with MOSFET and MC33198D
pin 2 permanently connected to battery. Vcc and other
functions can be switched off from the main battery line. See
figure 15.
Figure13.
Vbat
Vbat
Operation With Inductive Loads
The device can drive MOSFET in inductive loads
switching applications. In this case, a 1kΩ resistor should be
connected between source of the MOSFET and device pin 1.
The resistor will limit the current flowing into pin 1 and prevent
MC33198D from damage during switching off of the inductive
load. The gate voltage is internally clamped at - Vbe (0.6V
typical), then the Vds is limited to Vbat + Vbe + Vgson to
prevent excessive power dissipation in the MOSFET. The
load voltage is limited to Vbe + Vgson and allows reasonable
discharge current.
Switching On
The switching on of the MOSFET is ensured by the
internal charge pump. The charge pump response time
versus the MOSFET gate capacitance is shown in table
Dynamic Electrical Characteristics table .
4
1
1K
Rg
LOAD
3
Figure14.
5V
INPUT SIGNAL PIN7
0V
Switching Off
Here two cases have to be discussed ; the normal
switching off of the MOSFET and the switching off under fault
condition. The normal switching off is done by internal pull
down current sources. The value is 110µA and is in fact
composed of two current sources in parallel ; a 100µA and a
10µA source. The 10µA current is always connected to the
gate pin 4 as shown in device block diagram.
MC33198
Vgate WITHOUT Rgate
Vcc + 15V typ
0V
Vgate WITH Rgate
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MC33198
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This resistor will reduce in some way the charge pump
output voltage available for the MOSFET, but the device will
still provide enough Gate-to-Source voltage to maintain the
MOSFET on in good conditions. The resistor will mainly act as
an additional discharge current, which will reduce the
switching off time of the overall application. See the table 2
below and figure 11 which show the pin 4 voltage depending
on the additional gate resistor and the off switching time due
to this resistor.
If a very low switching time is needed, the resistor has to
be extremely low, resulting in low gate voltage not high
enough to ensure proper MOSFET operation. In this case, a
logic level MOSFET can be used. Logic level will operate with
Vgs of 5V with the same performance as a standard MOSFET
having a 12V Vgs. Care should be taken regarding maximum
gate to source voltage of a logic level MOSFET. An additional
zener might be necessary to prevent gate oxyde damages.
Reverse Battery
The device does not sustain reverse battery operation for
Vcc voltage greater than - 0,6V in magnitude. In application,
pin 5 should be protected from reverse battery by connecting
a diode in series with the Vbat line.
Figure15.
Vbat
Vbat
R drn
5
VCC
DRN 2
6 STATUS
GATE 4
1K
7 INPUT
Table 2 • Switching Off Characteristics with
SOURCE 1
GND
3
MOSFET Additional Gate Resistor
TIMER
8
LOAD
C
Rgate
VCC (V)
Vgate (V)
Toff
No R
7
16
450
10
23
700
14
28
750
20
34
780
7
14
160
10
22
230
14
27
230
20
33
220
7
13
100
10
21
160
68 kΩ
Pin 2 which is normally connected to resistor, can sustain
reverse battery operation, providing that the DRN resistor is
higher than 3,3K. A 1K resistor at pin 1 is also necessary to
limit the reverse current flowing through the MOSFET body
diode.
Figure16. MC33198 Gnd Disconnection Circuitry
Vbat
5V
39 kΩ
15 kΩ
14
26
160
20
32
150
7
11
30
10
17,5
50
14
24
50
Vbat
5
Device drive
circuitry and
interface
4
6
MC33198
IN
LOAD
7
1
3
8
Module Gnd
C
Q1
R1
20
28,5
50
NOTE 1 : Time from negative edge of input signal (Pin 7) to negative edge
of gate voltage (Pin 4) measured at 5V threshold.
NOTE 2 : Gate discharge time, not LOAD switching OFF time.
Additional circuitry
to present MOSFET
turn-on in case of module
Gnd disconnection
R1 = 3,3K
Q1 = 2N2222
NOTE 3 : TMOS used is Motorola MTP50N06, load 10Ω resistor.
Operation
When module Gnd is disconnected and if VBAT
connection is still present, pin 3 of MC33198 goes to about 2/3
of Vbat if additional circuitry is not inserted.
With R1/Q1, Gate/Source voltage of MOSFET is shorted
as soon as pin 3 voltage rises above Gnd level.
MC33198
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MC33198
Freescale
Semiconductor,
MC33091A AND
MC33198 COMPARISON Inc.
Introduction
The MC33091A and MC33198D are Motorola integrated
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
Both devices are pin-to-pin compatible. The MC33091A
has a stand-by mode activated when ever the Input (pin 7) is
in the low state.
In this case, the supply current is less than 300µA over
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.
In addition, the MC33198D can sense and report the
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
In case of a MOSFET over current condition, the
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.
The MC33091A monitors the Drain-to-Source voltage
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
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 Drainto-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.
The MC33198D feature differs in that the Drain-to-Source
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 latchedoff until the input is switched low (off) and turned back on
again.
Fault Status
Both devices report the fault status to the microcontroller
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
Both devices are powered from the battery line. Both
devices have an overvoltage shutdown greater than 20V.
The MC33198D incorporates an undervoltage shutdown
feature which switches off the MOSFET for battery voltages
less than 7V.
For More Information On This Product,
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MOTOROLA
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MC33198
Freescale Semiconductor, Inc...
Freescale Semiconductor, Inc.
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reliability, function or design. Motorola does not assume any liability arising out of the application or use of any
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whereupon Motorola shall determine availability and suitability of its products for the use intended. Motorola and
are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Employment opportunity/Affirmative
Action Employer.
MC33198
For More Information
On This Product,
MOTOROLA
Go to: www.freescale.com
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