LX1752 Datasheet, PDF (1/28 Pages) Microsemi Corporation – Dual Interleaving PWM Controller

LX1752
TM
®
Dual Interleaving PWM Controller
PRODUCTION DATA SHEET
GENERAL DESCRIPTION
The LX1752 is a dual output Internal gate drive circuitry provides 5V
synchronous buck controller using voltage for the external upper and lower N channel
mode PWM architecture.
MOSFETS.
The single input voltage supply feature Output voltages as low as 700mV, load
simplifies the design and offers a wide currents up to 15A per phase and efficiency
range of operation from 4.5 to 22 volts. of 93% can be achieved with the flexible
Each PWM has a Soft-Start pin for controller.
programming the output sequencing and Operating alone or with other LX1752’s
serves as the shutdown control.
on a bus, three multi-phase interleaving
Current limit threshold is set with a options are available: two PWM channels
single external resistor and protects the with 180° separation; three PWM channels
high-side and low-side MOSFETs by at 120° or four PWM channels at 90°. This
sensing the voltage drop generated from phasing is set by the tri-state input pin
R_DSON.
PSET. This architecture minimizes the
Each PWM channel has its own input capacitor requirements.
external feedback compensation for The entire power supply design occupies
performance optimization.
a small footprint with the LX1752’s low
profile 28 pin, MLP package of 4x5x1mm
(JEDEC MO-220).
KEY FEATURES
ƒ Dual PWM Controller,
Synchronous Operation
ƒ Voltage Mode PWM with
External Compensation
ƒ Single Input Supply, wide
range 4.5V to 22V
ƒ Precision Reference
ƒ Outputs as low as 700mV
ƒ Selectable PWM Frequency up
to 1.5Mhz
ƒ Synchronization Pin for PWM
Frequency
ƒ Independent and
Programmable Soft
Start/Enable for Power
Sequencing
ƒ Integrated High Current
MOSFET Drivers
ƒ Programmable Current Limit
ƒ Lossless Current Sensing for
Current Limit and Short Circuit
Protection
ƒ Pb-free, RoHS Compliant
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
APPLICATIONS
ƒ Multi-Output Power Supplies
ƒ Video Card Power Supplies
ƒ PC Peripherals
ƒ Set Top Boxes
ƒ Point of Load DC-DC
Converters
VIN 4.5V to 22V
SYNC
SHDN
PRODUCT HIGHLIGHT
VSX
VIN
HOX
VCCL
VCX
PSET
HRX
SSENX L_PX1_a7_r5_t 2
CSX
AGND
LOX
SYNC
PGX
SHDNX
RFREQ
EAX-
EAOX
PACKAGE ORDER INFO
T_A (°C)
Plastic MLPQ
LQ _{28 pin}
RoHS Compliant / Pb-free
0 to 85
LX1752CLQ
Note: Available in Tape & Reel. Append the letters “TR” to
the part number. (i.e. LX1752CLQ-TR)
VOUT
ONE OF 2 PWM SECTIONS
Copyright © 2007
Rev. 1.0, 2008-07-31
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
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