LT1158 Datasheet, PDF (1/20 Pages) Linear Technology – Half Bridge N-Channel Power MOSFET Driver

FEATURES
s _{Drives Gate of Top Side MOSFET Above V}⁺
s _{Operates at Supply Voltages from 5V to 30V}
s _{150ns Transition Times Driving 3000pF}
s _{Over 500mA Peak Driver Current}
s _{Adaptive Non-Overlap Gate Drives}
s _{Continuous Current Limit Protection}
s _{Auto Shutdown and Retry Capability}
s _{Internal Charge Pump for DC Operation}
s _{Built-In Gate Voltage Protection}
s _{Compatible with Current-Sensing MOSFETs}
s _{TTL/CMOS Input Levels}
s _{Fault Output Indication}
U
APPLICATIONS
s _{PWM of High Current Inductive Loads}
s _{Half Bridge and Full Bridge Motor Control}
s _{Synchronous Step-Down Switching Regulators}
s _{Three-Phase Brushless Motor Drive}
s _{High Current Transducer Drivers}
s _{Battery-Operated Logic-Level MOSFETs}
LT1158
Half Bridge N-Channel
Power MOSFET Driver
DESCRIPTION
A single input pin on the LT1158 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.
TYPICAL APPLICATION
+
10µF
PWM
0Hz TO
100kHz
+
1µF
0.01µF
1N4148
BOOST DR
V⁺
V⁺
BOOST
T GATE DR
T GATE FB
T SOURCE
INPUT
SENSE⁺
LT1158
ENABLE
SENSE^–
FAULT
B GATE DR
BIAS
B GATE FB
GND
24V
0.1µF
IRFZ34
+
500µF
LOW
ESR
+
R_SENSE
0.015Ω
–
LOAD
IRFZ34
Top and Bottom Gate Waveforms
V_IN = 24V
R_L = 12Ω
1158 TA02
LT1158 TA01
1