NCP1550_06 Datasheet, PDF (1/17 Pages) ON Semiconductor – 600 kHz PWM/PFM Step−Down DC−DC Controller

NCP1550
600 kHz PWM/PFM
Step−Down DC−DC
Controller
The NCP1550 is a monolithic micropower high frequency voltage
mode step−down controller IC, specially designed for battery operated
hand−held electronic products. With appropriate external P−type
MOSFET, the device can provide up to 2.0 A loading current with high
conversion efficiency. The device operates in Constant−Frequency
PWM mode at normal operation, that ensures low output ripple noise,
and which will automatically switch to PFM mode at low output loads
for higher efficiency. Additionally, value−added features of Chip
Enable to reduce IC Off−State current and integrated feedback resistor
network, make it the best choice for portable applications. The device is
designed to operate for voltage regulation with minimum external
components and board space. This device is available in a TSOP−5
package with six standard output voltage options.
Features
• High Efficiency 92%, Typical
• Low Quiescent Bias Current of 50 mA
(Typical at PFM Mode with No Load)
• Output Voltage Options from 1.8 V to 3.3 V
with High Accuracy $2.0%
• Low Output Voltage Ripple, 50 mV, Typical
• PWM Switching Frequency at 600 kHz
• Automatic PWM/PFM Switchover at Light Load Condition
• Very Low Dropout Operation, 100% Max. Duty Cycle
• Chip Enable Pin with On−Chip 150 nA Pullup Current Source
• Low Shutdown Current, 0.3 mA, Typical
• Input Voltage Range from 2.45 V to 5.5 V
• Built−in Soft−Start
• Internal Undervoltage Lockout (UVLO) Protection
• Low Profile and Minimum External Components
• Micro Miniature TSOP−5 Package
• Pb−Free Packages are Available
Typical Applications
• Personal Digital Assistant (PDA)
• Camcorders and Digital Still Camera
• Hand−Held Instrument
• Distributed Power System
• Computer Peripheral
• Conversion from Four NiMH or NiCd or One Lithium−ion Cells to
3.3 V/1.8 V
© Semiconductor Components Industries, LLC, 2006
1
July, 2006 − Rev. 8
http://onsemi.com
1
TSOP−5
SN SUFFIX
CASE 483
MARKING DIAGRAM
5
xxx AYW G
G
1
xxx = Specific Device Code
A = Assembly Location
Y = Year
W = Work Week
G = Pb−Free Package
(Note: Microdot may be in either location)
PIN CONNECTIONS
CE ₁
5 ^VIN
GND 2
V_{OUT 3}
4 ^EXT
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 16 of this data sheet.
Publication Order Number:
NCP1550/D