LX1736
TM
廬
V
REF
@
800mV, 900mA, 1.0MH
Z
PWM
P
RODUCTION
D
ATA
S
HEET
DESCRIPTION
KEY FEATURES
Few External Components
800mv Internal Reference
Tight Regulation over Line,
Load and Temperature
4.5V to 5.5V Input Range
Internal Soft Start Controls
Inrush Current
High Efficiency
Low Quiescent Current, 600渭A
Fully Fault Protected
Thin MO-229, 6-Pin Package
WWW .
Microsemi
.C
OM
The LX1736 operates as a Current
Mode PWM Buck regulator that
switches to PFM mode under light
loads. The entire regulator function is
implemented with only a few, low-
cost external components.
The LX1736 responds quickly to
dynamic load changes using a high
bandwidth error amplifier and internal
compensation. Tight output voltage
regulation is maintained with the
temperature compensated 800mV,
bandgap reference achieving +/-3.5%
regulation tolerance for all line, load
and thermal conditions. The output
voltage is easily programmed, from
800mV to 90% of V
IN
with two
external resistors
The regulator is capable of providing an
output load current of 900mA and has
no minimum load current requirement
for stable operation. Current limit
senses on a cycle-by cycle basis to
protect the switch. Power conversion
efficiency is maximized with PFM
mode of operation and low regulator
quiescent current.
The LX1736 operational supply voltage
range covers 4.0V to 6.0V, features
include: power on delay; soft start to
limit inrush currents and thermal
shutdown during fault conditions.
The 6-pin JEDEC MO-229 package
provides a small form factor and low
profile at 3x3x1mm with excellent
power dissipation capability on surface
mount PCB鈥檚.
APPLICATIONS
Point of Load Regulation
DSP, ASIC and Core Voltage
Supplies
Hard Disk Drives
Set Top Boxes
RoHS compliant product
IMPORTANT:
For the most current data, consult
MICROSEMI鈥檚
website:
http://www.microsemi.com
PRODUCT HIGHLIGHT
4V to 6V
Efficiency
@
V
IN=5V,
4
VPWR
N/C
6
95%
3.3uH
1.25V
@
875mA
VO=1.25V (Lower)
VO=3.3V (Upper)
85%
75%
65%
30uF
17.8K
Ground
Plane
Tie-in
5
4.7uF
VCC
SW
3
10.0K
2
GND
FB
1
55%
45%
35%
25%
1
10
100
OUTPUT CURRENT, mA
1000
Figure 1 鈥?/div>
LX1736 Application Circuit and Typical Efficiency Performance
PACKAGE ORDER INFO
LX1736
LX1736
T
A
(擄C)
0 to 125
LD
Plastic MLPD
6 pin 3mm x 3mm
LX1736CLD
Package Marking
RoHS Compliant / Pb-free
Note: Available in Tape & Reel. Append the letters 鈥淭R鈥?to
the part number. (i.e. LX1736CLD-TR)
1736
xxxx
MSC
Page 1
Copyright
漏
2005
Rev. 1.0, 1/3/2007
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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