LM27222_15 Datasheet, PDF (1/16 Pages) Texas Instruments – LM27222 High-Speed 4.5A Synchronous MOSFET Driver

LM27222
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SNVS306B – SEPTEMBER 2004 – REVISED MARCH 2013
LM27222 High-Speed 4.5A Synchronous MOSFET Driver
Check for Samples: LM27222
FEATURES
1
•2 Adaptive Shoot-through Protection
• 10ns Dead Time
• 8ns Propagation Delay
• 30ns Minimum On-time
• 0.4Ω Pull-down and 0.9Ω Pull-up Drivers
• 4.5A Peak Driving Current
• MOSFET Tolerant Design
• 5µA Quiescent Current
• 30V Maximum Input Voltage in Buck
Configuration
• 4V to 6.85V Operating Voltage
• SOIC-8 and WSON Packages
APPLICATIONS
• High Current Buck And Boost Voltage
Converters
• Fast Transient DC/DC Power Supplies
• Single Ended Forward Output Rectification
• CPU And GPU Core Voltage Regulators
DESCRIPTION
The LM27222 is a dual N-channel MOSFET driver
designed to drive MOSFETs in push-pull
configurations as typically used in synchronous buck
regulators. The LM27222 takes the PWM output from
a controller and provides the proper timing and drive
levels to the power stage MOSFETs. Adaptive shoot-
through protection prevents damaging and efficiency
reducing shoot-through currents, thus ensuring a
robust design capable of being used with nearly any
MOSFET. The adaptive shoot-through protection
circuitry also reduces the dead time down to as low
as 10ns, ensuring the highest operating efficiency.
The peak sourcing and sinking current for each driver
of the LM27222 is about 3A and 4.5Amps
respectively with a Vgs of 5V. System performance is
also enhanced by keeping propagation delays down
to 8ns. Efficiency is once again improved at all load
currents by supporting synchronous, non-
synchronous, and diode emulation modes through the
LEN pin. The minimum output pulse width realized at
the output of the MOSFETs is as low as 30ns. This
enables high operating frequencies at very high
conversion ratios in buck regulator designs. To
support low power states in notebook systems, the
LM27222 draws only 5µA from the 5V rail when the
IN and LEN inputs are low or floating.
Typical Application
VCC
4V to 6.85V
R1
C1
D1
U1
6
V_CC
3
CB
(to controller) 5
LEN
HG ²
(to controller) 4
LM27222
IN
SW
1
8 _GND
LG ⁷
C2
0.33 PF
V_IN
Q1
up to 30V
+
C3
L1
V_OUT
Q2
+
C4
0.5V to
Vin - 0.5V
1
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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