LX1742 Datasheet, PDF (1/13 Pages) Microsemi Corporation – High Efficiency High Voltage Boost Controller

INTEGRATED PRODUCTS
LX1742
High Efficiency High Voltage Boost Controller
PRODUCTION DATA SHEET
DESCRIPTION
The LX1742 is a compact high The input voltage ranges from 1.6V to
efficiency step-up boost controller. 6.0V, allowing for a wide selection of
Featuring a pseudo-hysteretic pulse system battery voltages. Start-up
frequency modulation topology, the operation is guaranteed at 1.6V input
LX1742 was designed for maximum The LX1742 is capable of achieving
efficiency, reduced board size, and output voltages as high as 25V and the
minimal cost.
output voltage is easily programmed
Utilizing an internal N-Channel using two external resistors in
MOSFET, the LX1742 offers conjunction with the feedback pin.
designers maximum flexibility with The LX1742 has an additional feature
respect to efficiency and cost. The for simple dynamic adjustment of the
LX1742 provides several design output voltage (i.e., up to ±15% of the
enhancements that improve overall nominal output voltage). Voltage
performance under very light load adjustment is achieved via an analog
currents by implementing control reference signal or a direct PWM input
circuitry that is optimized for portable signal applied to the ADJ pin. Any
systems - thus providing a quiescent PWM amplitude is easily
supply current of only 80µA (typ) and accommodated with a single external
a shutdown current of less than 1µA. resistor.
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
PRODUCT HIGHLIGHT
L₁
47µH
UPS530
SW
IN
OUT
SHDN
LX1742
C₂ *
1nF
ADJ
FB
CS
GND
R_CS
1kΩ
V_BAT = (1.6V to 6.0V)
V_OUT = 18V ± 15%
(For Contrast Adjustment)
R₁
1MΩ
C₁
4.7µF
R₂
72kΩ
KEY FEATURES
ƒ 80% Typical Efficiency
ƒ 80µA Typical Quiescent Supply
Current
ƒ Externally Programmable Peak
Inductor Current Limit For
Maximum Efficiency
ƒ Logic Controlled Shutdown
ƒ < 1.0 µA Shutdown Current (typ)
ƒ Dynamic Output Voltage
Adjustment Via Analog
Reference Or Direct PWM Input
ƒ 8-Pin MSOP Package
APPLICATIONS/BENEFITS
ƒ Pagers
ƒ Wireless Phones
ƒ PDAs
ƒ Handheld Computers
ƒ General LCD Bias Applications
ƒ LED Driver
R_PWM
625kΩ
100kHz
V_PWM = 3.0V
Copyright © 2000
Rev. 1.0b, 2005-03-03
PACKAGE ORDER INFO
T_A (°C)
Plastic MSOP
DU _8-Pin
RoHS Compliant / Pb-free
Transition DC: 0432
0 to 70
LX1742CDU
Note: Available in Tape & Reel. Append the letters “TR” to the
part number. (i.e. LX1742CDU-TR)
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
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