NCP1450A_05 Datasheet, PDF (1/22 Pages) ON Semiconductor – PWM Step−up DC−DC Controller

NCP1450A
PWM Step−up DC−DC
Controller
The NCP1450A series are PWM step−up DC−DC switching
controller that are specially designed for powering portable equipment
from one or two cells battery packs. The NCP1450A series have a
driver pin, EXT pin, for connecting to an external transistor. Large
output currents can be obtained by connecting a low ON−resistance
external power transistor to the EXT pin. The device will
automatically skip switching cycles under light load condition to
maintain high efficiency at light loads. With only six external
components, this series allows a simple means to implement highly
efficient converter for large output current applications.
Each device consists of an on−chip Pulse Width Modulation (PWM)
oscillator, PWM controller, phase−compensated error amplifier,
soft−start, voltage reference, and driver for driving external power
transistor. Additionally, a chip enable feature is provided to power
down the converter for extended battery life.
The NCP1450A device series are available in the TSOP−5 package
with five standard regulated output voltages. Additional voltages that
range from 1.8 V to 5.0 V in 100 mV steps can be manufactured.
Features
• High Efficiency 86% at I_O = 200 mA, V_IN = 2.0 V, V_OUT = 3.0 V
88% at I_O = 400 mA, V_IN = 3.0 V, V_OUT = 5.0 V
• Low Startup Voltage of 0.9 V typical at I_O = 1.0 mA
• Operation Down to 0.6 V
• Five Standard Voltages: 1.9 V, 2.7 V, 3.0 V, 3.3 V, 5.0 V with High
Accuracy ± 2.5%
• Low Conversion Ripple
• High Output Current up to 1000 mA
(3.0 V version at V_IN = 2.0 V, L = 10 mH, C_OUT = 220 mF)
• Fixed Frequency Pulse Width Modulation (PWM) at 180 kHz
• Chip Enable Pin with On−chip 150 nA Pullup Current Source
• Low Profile and Micro Miniature TSOP−5 Package
• Pb−Free Packages are Available
Typical Applications
• Personal Digital Assistant (PDA)
• Electronic Games
• Portable Audio (MP3)
• Digital Still Cameras
• Handheld Instruments
http://onsemi.com
5
1
TSOP−5
SN SUFFIX
CASE 483
MARKING DIAGRAM AND
PIN CONNECTIONS
CE 1
5 EXT
OUT 2
NC 3
4 GND
(Top View)
xxx =Specific Device Marking
A = Assembly Location
Y = Year
W = Work Week
G = Pb−Free Package
(Note: Microdot may be in either location)
ORDERING INFORMATION
See detailed ordering and shipping information in the ordering
information section on page 3 of this data sheet.
© Semiconductor Components Industries, LLC, 2005
1
December, 2005 − Rev. 7
Publication Order Number:
NCP1450A/D