LX717 5
3V-5.5V, 3.5A Step Down
PWM Switching Regulator
Features
3.5A Step-down Regulator
Description
Operational Input Supply Voltage Range:
LX7175 is a step-down PWM Switching Regulator
3V-5.5V
IC with integrated high side P-CH and low side N-
Integrated PMOS and NMOS
CH MOSFETs. The IC operates using a hysteretic
Load Current from zero to 3.5A
control topology with a full load switching
frequency of 1.4MHz allowing small output filter
1.4MHz Switching Frequency
components while maintaining excellent dynamic
SKIP Pulse to Improve Light Load
load response.
Efficiency
The operational input voltage range of LX7175 is
Open VReg Type 0 LV Compatible
from 3V to 5.5V and it has two modes of operation
Input UVLO Protection
selected externally by MODE pin. When MODE
Enable Pin
pin is high, it operates in continuous PWM
operation and when it is tied low, it operates in Power Good
Power Save Mode (PSM) with automatic transition
Internal Soft-start
between PWM and PSM mode depending on the
Cycle-by-Cycle Over Current Protection
load current. This allows the converters efficiency
Latch Off Operation Under Output Short.
to remain high when load current drops.
RoHS Compliant for Pb-free
In the shutdown mode, the ICs current consumption
is reduced to less than 1A and the output capacitor
is discharged.
Applications
Other features of the part are: a) cycle-by-cycle
Small Battery Operated Devices
current limit followed by latch off, b) thermal
HDD
protection with hysteresis, c) internal digital soft
Set-Top Box
start, d) and Power Good function.
LCD TVs
Notebook/Netbook
Routers
Video Cards
PC Peripherals
PoE Powered Devices
VIN
CVIN
10F, X5R
2, 3
VIN
R
mode
L
RPgood VOUT
8 6, 7
MODE SW
1H
R1 COUT
C1
1% 2x22F, X5R
LX7175
9 1
PGOOD FB
R2
1%
EN
10 4, 5
on EN GND
off
PAD
Figure 1 Typical Application of LX7175
July 2013 Rev. 1.2 www.microsemi.com 1
2013 Microsemi Corporation 3V-5.5V, 3.5A Step Down PWM Switching Regulator
Pin Configuration and Pinout
1 10
FB EN
2 9
PGOOD
VIN
Thermal
3 8
Pad MODE
VIN
(GND)
4 7
SW
GND
5 6
GND
SW
Figure 2 Pinout DFN 3x3 10L Top View
Marking: Line1 7175
Line2 Date / Lot Code
Line3 * MSC ( * is the pin 1 dot )
Ordering Information
Ambient
Type Package Part Number Packaging Type
Temperature
LX7175CLD Bulk / Tube
RoHS Compliant,
-10C to 85C DFN 3X3 10L
Pb-free
LX7175CLD-TR Tape and Reel
2