mc33198dr2 Freescale Semiconductor, Inc, mc33198dr2 Datasheet - Page 13

• Manufacturer Part Number: mc33198dr2
• Description: Automotive High-side Tmos Driver
• Manufacturer: Freescale Semiconductor, Inc

the switch off time can be long, compared to the on-switching
time response. This is due to the 110mA gate discharge
current. To improve this parameter, a resistor can be added
in parallel with the gate of the MOSFET. See
17.
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
switch off time of the overall application. See the
Switching Off Characteristics with MOSFET Additional Gate
Resistor
depending on the additional gate resistor and the off
switching time due to this resistor.
be an extremely low value, resulting in low gate voltage not
high enough to ensure proper MOSFET operation. In this
case, a logic level MOSFET can be used. Logic levels will
operate with V
standard MOSFET having a 12V V
regarding the maximum gate to source voltage of a logic level
MOSFET. An additional zener might be necessary to prevent
gate oxide damage.
Analog Integrated Circuit Device Data
Freescale Semiconductor
This resistor will reduce (in some way) the charge pump
If a very low switching time is needed, the resistor has to
INPUT SIGNAL PIN7
Vcc + 15V typ
Figure 16. Schematic with R
and
0V
5V
0V
Figure 17. R
Figure
GS
3
of 5.0V, with the same performance as a
Vbat
15, which show the pin 4 voltage
GATE
Vgate WITH Rgate
1
4
Signal Comparison
1K
GS
Rg
. Care should be taken
GATE
Vgate WITHOUT Rgate
Resistor
Vbat
Figures 16
Toff
LOAD
Table 6,
Toff
and
Table 6. Switching Off Characteristics with MOSFET
REVERSE BATTERY
V
pin 5 should be protected from reverse battery by connecting
a diode in series with the V
Notes
Vbat
CC
R
1.
2.
3.
The device does not sustain reverse battery operation for
GATE
voltages greater than - 0.6V in magnitude. In application,
68 kΩ
39 kΩ
15 kΩ
No R
Time from negative edge of input signal (Pin 7) to negative
edge of gate voltage (Pin 4) measured at 5V threshold.
Gate discharge time, not LOAD switching OFF time.L
TMOS used is Freescale MTP50N06, load 10Ω resistor.
6 STATUS
7 INPUT
(R
G
Additional Gate Resistor
)
Figure 18. 33198 Reverse Battery
GND
3
VCC
VCC (V)
5
7.0
7.0
7.0
7.0
10
14
20
10
14
20
10
14
20
10
14
20
TIMER
SOURCE 1
8
GATE
DRN
C
BAT
line.
2
4
FUNCTIONAL DESCRIPTION
V
GATE
17.5
28.5
16
23
28
34
14
22
27
33
13
21
26
32
11
24
1 K
R
(V)
drn
INTRODUCTION
Vbat
T
LOAD
OFF
450
700
750
780
160
230
230
220
100
160
160
150
30
50
50
50
(µsec)
33198
13