Half Bridge N-Channel Power MOSFET Driver

A single input pin on the LT1158 synchronously controls two N-channel power MOSFETs in a totem pole configuration. 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 VDS 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 operation. The gate-to-source voltages are internally limited to 14.5V when operating at higher supply voltages.

Applications

* 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

* 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