Linear LTC4449高速同步N-MOSFET驱动方案
Linear 公司的LTC4449是高速同步N-MOSFET驱动器,VCC工作电压4-6.5V,输入电压达38V,3.2A上拉峰值电流, 4.5A下拉峰值电流,主要用在分布电源和高密度电源模块.本文介绍LTC4449主要特性,方框图以及2相1.2V/50A应用电路图.
LTC4449: High Speed Synchronous N-Channel MOSFET Driver
The LTC®4449 is a high frequency gate driver that is designed to drive two N-Channel MOSFETs in a synchronous DC/DC converter. The powerful rail-to-rail driver capability reduces switching losses in MOSFETs with high gate capacitance.
The LTC4449 features a separate supply for the input logic to match the signal swing of the controller IC. If the input signal is not being driven, the LTC4449 activates a shutdown mode that turns off both external MOSFETs. The input logic signal is internally level-shifted to the bootstrapped supply, which functions at up to 42V above ground.
The LTC4449 contains undervoltage lockout circuits on both the driver and logic supplies that turn off the external MOSFETs when an undervoltage condition is present. An adaptive shoot-through protection feature is also built-in to prevent the power loss resulting from MOSFET crossconduction current.
The LTC4449 is available in the 2mm × 3mm DFN package.
LTC4449主要特性:
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