LT1158CS LINER [Linear Technology], LT1158CS Datasheet - Page 5

• Manufacturer Part Number: LT1158CS
• Description: Half Bridge N-Channel Power MOSFET Driver
• Manufacturer: LINER [Linear Technology]

PI FU CTIO S
Pin 1 (Boost Drive): Recharges and clamps the bootstrap
capacitor to 14.5V higher than pin 13 via an external diode.
Pin 2 (V
the ground pin 7.
Pin 3 (Bias): Decouple point for the internal 2.6V bias
generator. Pin 3 cannot have any external DC loading.
Pin 4 (Enable): When left open, the LT1158 operates
normally. Pulling pin 4 low holds both MOSFETs off
regardless of the input state.
Pin 5 (Fault): Open collector NPN output which turns on
when V12 – V11 exceeds the fault conduction threshold.
Pin 6 (Input): Taking pin 6 high turns the top MOSFET on
and bottom MOSFET off; pin 6 low reverses these states.
An input latch captures each low state, ignoring an ensu-
ing high until pin 13 has gone below 2.6V.
Pin 8 (Bottom Gate Feedback): Must connect directly to
the bottom power MOSFET gate. The top MOSFET turn-on
is inhibited until pin 8 has discharged to 1.5V. A hold-on
current source also feeds the bottom gate via pin 8.
Pin 9 (Bottom Gate Drive): The high current drive point
for the bottom MOSFET. When a gate resistor is used, it is
inserted between pin 9 and the gate of the MOSFET.
TYPICAL PERFORMANCE CHARACTERISTICS
300
250
150
400
350
200
100
50
U
0
Top Gate Rise Time
0
+
5
): Main supply pin; must be closely decoupled to
U
10
SUPPLY VOLTAGE (V)
15
C
C
C
GATE
GATE
GATE
20
U
= 10000pF
= 3000pF
= 1000pF
25
30
W
LT1158 G13
35
U
40
250
150
400
350
300
200
100
50
0
Top Gate Fall Time
0
5
10
SUPPLY VOLTAGE (V)
15
C
C
C
GATE
GATE
GATE
20
Pin 10 (V
nected to the same supply as pin 2.
Pin 11 (Sense Negative): The floating reference for the
current limit comparator. Connects to the low side of a
current shunt or Kelvin lead of a current-sensing MOSFET.
When pin 11 is within 1.2V of V
Pin 12 (Sense Positive): Connects to the high side of the
current shunt or sense lead of a current-sensing MOSFET.
A built-in offset between pins 11 and 12 in conjunction
with R
Pin 13 (Top Source): Top side driver return; connects to
MOSFET source and low side of the bootstrap capacitor.
Pin 14 (Top Gate Feedback): Must connect directly to the
top power MOSFET gate. The bottom MOSFET turn-on is
inhibited until V14 – V13 has discharged to 1.75V. An on-
chip charge pump also feeds the top gate via pin 14.
Pin 15 (Top Gate Drive): The high current drive point for
the top MOSFET. When a gate resistor is used, it is inserted
between pin 15 and the gate of the MOSFET.
Pin 16 (Boost): Top side driver supply; connects to the
high side of the bootstrap capacitor and to a diode either
from supply (V
= 3000pF
= 10000pF
= 1000pF
25
SENSE
30
LT1158 G14
35
+
): Bottom side driver supply; must be con-
sets the top MOSFET short-circuit current.
40
+
< 10V) or from pin 1 (V
800
100
700
600
500
400
300
200
0
0
Transition Times vs R
V
C
10
+
GATE
= 12V
+
20
= 3000pF
, current limit is inhibited.
GATE RESISTANCE ( )
30
RISE TIME
40
50
+
> 10V).
60
LT1158
Gate
FALL TIME
70
80
LT1158 G15
90
5
100