LX1912
TM
廬
VREF @ 800mV, 1.0A, 1.2MHz PWM
P
RODUCTION
D
ATA
SHEET
DESCRIPTION
KEY FEATURES
Internal Reference 800mv 鹵2%
Accuracy (Line and Temp.)
4.0V to 6.0V Input Range
Internal Soft Start
Adj. Output From 0.8V to 90%
of V
IN
Output Current up to 1.0A
Quiescent Current < 550渭A,
Typical @ 23擄C
1.2MHz PWM Frequency
Over Voltage Protection
APPLICATIONS
WWW .
Microsemi
.C
OM
The LX1912 operates as a Current
Mode PWM Buck regulator that
switches to PFM mode with light
loads. The entire regulator function is
implemented with few external
components.
The LX1912 responds quickly to
dynamic load changes using a high
bandwidth error amplifier and internal
compensation. Tight output voltage
regulation is maintained with the
compensated 800mV, 鹵2% reference
(line and temp regulation). With two
external resistors the output voltage is
easily programmed, from 800mV to
90% of V
IN
.
The regulator is capable of providing
an output load current of 1.0A, has no
minimum load current requirement for
stable operation. Current limit is
cycle-by-cycle to protect the switch.
Power conversion efficiency is
maximized with low regulator IQ and
PFM mode of operation
The LX1912 operational 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 TSOT package provides a
small form factor with excellent power
dissipation capability.
Portable Microprocessor Core
Voltage Supplies
5V to 3V
RoHS Compliant Product
IMPORTANT:
For the most current data, consult
MICROSEMI鈥檚
website:
http://www.microsemi.com
PRODUCT HIGHLIGHT
4V to 6V
95%
EFFICIENCY (VIN = 5V, VOUT @ 3.3V)
VPWR
4.7碌F
2.7碌H
90%
SW
31.6K
3.3V @ 1.0A
EFFICIENCY
85%
80%
75%
70%
65%
VCC
LX1912
Part
GND
N.C.
FB
30碌F
10K
60%
55%
50%
0.01
0.10
1.00
OUTPUT CURRENT (Amps)
Figure 1 鈥?/div>
LX1912 Circuit Topology and Typical Efficiency Performance
PACKAGE ORDER INFO
T
A
(擄C)
0 to +70
Output
Input Voltage Voltage
Range
4.0V 鈥?6.0V Adjustable
SG
Plastic TSOT
6-Pin
LX1912CSG
Part Marking
LX1912
LX1912
RoHS Compliant / Pb-free
1912
Note: Available in Tape & Reel. Append the letters 鈥淭R鈥?to the part number. (i.e. LX1912CSG-TR)
Copyright
漏
2005
Rev. 1.0, 2006-09-06
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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