
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
Copyright
2000
Rev. 1.1c, 2005-03-03
W
M
.
C
LX1732
High Current PFM Boost Converter
P
RODUCTION
D
ATA
S
HEET
I N T E G R A T E D P R O D U C T S
D E S C R I P T I O N
The LX1732 is a compact, high
efficiency, step-up DC-DC boost
regulator
implemented
BiCMOS process technology. This
device features variable frequency
operation and a built in N-channel
MOSFET
power
optimal functioning in low voltage
portable systems.
Start-up operation is guaranteed
from 1.1V inputs (at light load)
and the input voltage can be as low
as 0.7V after start-up. This
attribute allows the LX1732 to
operate in an extended power-
savings mode, supplying (data)
critical system components, even
after battery capacity no longer
supports normal operation.
in
a
switch
for
The output voltage programming
range of 2.2V to 5V, requires only
two external resistors via the
feedback pin (see Figure 1.0).
Output load currents of up to
200mA are achievable and the
internal MOSFET is capable of
switching up to a 1A current limit.
Quiescent current during operation
is 200
μ
A (max) and in shutdown-
mode drops to a mere 1
μ
A thus
maximizing overall battery life-
time.
The LX1732 features a low
battery-detect circuitry that alerts
system power management of low
input
voltages
portable systems to enter a power-
savings mode (e.g., to protect data)
thus
allowing
IMPORTANT:
For the most current data, consult
MICROSEMI
’s website:
http://www.microsemi.com
K E Y F E A T U R E S
88% Efficiency
200μA Quiescent Current
0.1μA Logic Shutdown
Low-Battery Detector
8-Pin MSOP Package
APPLICAT IONS /BENEFIT S
Pagers
Wireless Phones
Hand-Held Computers
PDAs
RF Tags
Two-cell Alkaline Battery
Applications
Single-cell Lithium Ion 5V
Boost
P R O D U C T H I G H L I G H T
V
BAT
V
OUT
LX1732
GND
VC
FB
SW
SHDN
IN
LBI
LBO
L
D
C
OUT
R
1
R
2
R
3
R
4
C
IN
50%
60%
70%
80%
90%
100%
0
25
50
75
Output Current
100
125
150
175
200
E
Figure 1
– LX1732 General Circuit Topology and Typical Efficiency Performance
PACK AGE ORDER INFO
DU
T
A
(
°
C)
Plastic MSOP
8-Pin
RoHS Compliant / Pb-free
Transition DC: 0432
LX1732CDU
0 to 70
Note: Available in Tape & Reel. Append the letters “TR” to the part
number. (i.e. LX1732CDU-TR)
L
X
1
7
3
2