NCP1530_05 Datasheet, PDF (1/16 Pages) ON Semiconductor – 600 mA PWM/PFM Step-Down Converter with External Synchronization Pin

NCP1530
600 mA PWM/PFM
Step−Down Converter with
External Synchronization Pin
The NCP1530 is a PWM/PFM non−synchronous step−down
(Buck) DC−DC converter for usage in systems supplied from 1−cell
Li−ion, or 2 or more cells Alkaline/NiCd/NiMH batteries. It can
operate in Constant−Frequency PWM mode or PWM/PFM mode in
which the controller will automatically switch to PFM mode
operation at low output loads to maintain high efficiency. The
switching frequency can also be synchronized to external clock
between 600 kHz and 1.2 MHz. The maximum output current is up
to 600 mA. Applying an external synchronizing signal to SYN pin
can supersede the PFM operation.
The NCP1530 consumes only 47 mA (typ) of supply current
(V_OUT = 3.0 V, no switching) and can be forced to shutdown mode by
bringing the enable input (EN) low. In shutdown mode, the regulator
is disabled and the shutdown supply current is reduced to
0.5 mA (typ). Other features include built−in undervoltage lockout,
internal thermal shutdown, an externally programmable soft−start
time and output current limit protection. The NCP1530 operates
from a maximum input voltage of 5.0 V and is available in a space
saving, low profile Micro8™ package.
Features
• Pb−Free Package is Available
• High Conversion Efficiency, up to 92% at V_IN = 4.3 V,
V_OUT = 3.3 V, I_OUT = 300 mA
• Current−Mode PWM Control
• Automatic PWM/PFM Mode for Current Saving at Low Output Loads
• Internal Switching Transistor Support 600 mA Output Current
(V_IN = 5.0 V, V_OUT = 3.3 V)
• High Switching Frequency (600 kHz), Support Small Size Inductor
and Capacitor, Ceramic Capacitors Can be Used
• Synchronize to External Clock Signal up to 1.2 MHz
• 100% Duty Cycle for Maximum Utilization of the Supply Source
• Programmable Soft−Start Time through External Chip Capacitor
• Externally Accessible Voltage Reference
• Built−In Input Undervoltage Lockout
• Built−In Output Overvoltage Protection
• Power Saving Shutdown Mode
• Space Saving, Low Profile Micro8 Package
Typical Applications
• PDAs
• Digital Still Camera
• Cellular Phone and Radios
• Portable Test Equipment
• Portable Scanners
• Portable Audio Systems
http://onsemi.com
8
1
MARKING
DIAGRAM
Micro8]
DM SUFFIX
CASE 846A
xxxx
ALYW
xxxx = Specific Device Code
A = Assembly Location
L = Wafer Lot
Y = Year
W = Work Week
PIN CONNECTIONS
V_IN 1
SYN 2
SS 3
GND ₄
(Top View)
8 LX
7 VREF
6 V_OUT
5 EN
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 14 of this data sheet.
© Semiconductor Components Industries, LLC, 2005
1
January, 2005 − Rev. 4
Publication Order Number:
NCP1530/D