LM2725/LM2726 High Speed Synchronous MOSFET Drivers
November 2000
LM2725/LM2726
High Speed Synchronous MOSFET Drivers
General Description
The LM2725/LM2726 is a family of dual MOSFET drivers
that can drive both the top MOSFET and bottom MOSFET in
a push-pull structure simultaneously. It takes a logic level
PWM input and splits it into two complimentary signals with
a typical 20ns dead time in between. The built-in
shoot-through protection circuitry prevents the top and bot-
tom FETs from turning on simultaneously. With a bias volt-
age of 5V, the peak sourcing and sinking current for each
driver of the LM2725 is about 1.2A and that of the LM2726 is
about 3A. In an SO-8 package, each driver is able to handle
50mA
average
current.
Input
UVLO
(Under-Voltage-Lock-Out) ensures that all the driver outputs
stay low until the supply rail exceeds the power-on threshold
during system power on, or after the supply rail drops below
power-on threshold by a specified hysteresis during system
power down. The cross-conduction protection circuitry de-
tects both the driver outputs and will not turn on a driver until
the other driver output is low. The top gate bias voltage
needed by the top MOSFET can be obtained through an
external bootstrap structure. Minimum pulse width is as low
as 55ns.
Features
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High peak output current
Adaptive shoot-through protection
36V SW pin absolute maximum voltage
Input Under-Voltage-Lock-Out
Typical 20ns internal delay
Plastic 8-pin SO package
Applications
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High Current DC/DC Power Supplies
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High Input Voltage Switching Regulators
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Microprocessors
Typical Application
DS200072-1
Connection Diagram
8-Lead Small Outline Package
DS200072-2
Top View
漏 2000 National Semiconductor Corporation
DS200072
www.national.com
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