June 2008 Rev 2 1/17
1
L6743
L6743Q
High current MOSFET driver
Features
■ Dual MOSFET driver for synchronous rectified
converters
■ High driving current for fast external MOSFET
switching
■ Integrated bootstrap diode
■ High frequency operation
■ Enable pin
■ Adaptive dead-time management
■ Flexible gate-drive: 5 V to 12 V compatible
■ High-impedance (HiZ) management for output
stage shutdown
■ Preliminary OV protection
■ SO-8 and DFN10 3x3 packages
Applications
■ High current VRM / VRD for desktop / server /
workstation CPUs
■ High current and high efficiency DC / DC
converters
Description
L6743, L6743Q is a flexible, high-frequency dual-
driver specifically designed to drive N-channel
MOSFETs connected in synchronous-rectified
buck topology.
Combined with ST PWM controllers, the driver
allows implementing complete voltage regulator
solutions for modern high-current CPUs and
DCDC conversion in general. L6743, L6743Q
embeds high-current drivers for both high-side
and low-side MOSFETS. The device accepts
flexible power supply (5 V to 12 V) to optimize the
gate-drive voltage for High-Side and Low-Side
maximizing the System Efficiency.
The Bootstrap diode is embedded saving the use
of external diodes. Anti shoot-through
management avoids high-side and low-side
MOSFET to conduct simultaneously and,
combined with Adaptive Dead-Time control,
minimizes the LS body diode conduction time.
L6743, L6743Q embeds Preliminary OV
Protection: after Vcc overcomes the UVLO and
while the device is in HiZ, the LS MOSFET is
turned ON to protect the load in case the output
voltage overcomes a warning threshold protecting
the output against HS failures.
The driver is available is SO-8 and DFN10 3x3
packages
SO-8
DFN10 3x3
Table 1. Device summary
Order code Package Packaging
L6743 SO-8 Tube
L6743TR SO-8 Tape and reel
L6743Q DFN10 Tube
L6743QTR DFN10 Tape and reel
www.st.com
