LT1158
Half Bridge N-Channel
Power MOSFET Driver
FEATURES
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DESCRIPTION
A single input pin on the LT
®
1158 synchronously controls
two N-channel power MOSFETs in a totem pole configura-
tion. Unique adaptive protection against shoot-through
currents eliminates all matching requirements for the two
MOSFETs. This greatly eases the design of high efficiency
motor control and switching regulator systems.
A continuous current limit loop in the LT1158 regulates
short-circuit current in the top power MOSFET. Higher
start-up currents are allowed as long as the MOSFET V
DS
does not exceed 1.2V. By returning the
FAULT
output to
the enable input, the LT1158 will automatically shut down
in the event of a fault and retry when an internal pull-up
current has recharged the enable capacitor.
An on-chip charge pump is switched in when needed to
turn on the top N-channel MOSFET continuously. Special
circuitry ensures that the top side gate drive is safely
maintained in the transition between PWM and DC opera-
tion. The gate-to-source voltages are internally limited to
14.5V when operating at higher supply voltages.
L,
LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners. Protected by U.S. Patents including
5365118.
Drives Gate of Top Side MOSFET Above V
+
Operates at Supply Voltages from 5V to 30V
150ns Transition Times Driving 3000pF
Over 500mA Peak Driver Current
Adaptive Non-Overlap Gate Drives
Continuous Current Limit Protection
Auto Shutdown and Retry Capability
Internal Charge Pump for DC Operation
Built-In Gate Voltage Protection
Compatible with Current-Sensing MOSFETs
TTL/CMOS Input Levels
Fault Output Indication
APPLICATIONS
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PWM of High Current Inductive Loads
Half Bridge and Full Bridge Motor Control
Synchronous Step-Down Switching Regulators
Three-Phase Brushless Motor Drive
High Current Transducer Drivers
Battery-Operated Logic-Level MOSFETs
TYPICAL APPLICATION
24V
1N4148
Top and Bottom Gate Waveforms
BOOST
T GATE DR
T GATE FB
T SOURCE
0.1μF
IRFZ34
BOOST DR
+
10μF
V
+
V
+
+
500μF
LOW
ESR
PWM
0Hz TO
100kHz
INPUT
LT1158
SENSE
+
+
R
SENSE
0.015Ω
LOAD
V
IN
= 24V
R
L
= 12Ω
1158 TA02
+
1μF
ENABLE
FAULT
BIAS
SENSE
–
B GATE DR
B GATE FB
GND
–
IRFZ34
0.01μF
LT1158 TA01
1158fb
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LINEAR_DIMENSIONS [ LINEAR DIMENSIONS SEMICONDUCTOR ]
