NCP1500 Datasheet, PDF (1/12 Pages) ON Semiconductor – Dual Mode PWM/Linear BUCK Converter

NCP1500
Dual Mode PWM/Linear
BUCK Converter
The NCP1500 is a dual mode converter that operates as either a
pulse width modulated (PWM) buck converter or as a linear regulator.
The converter automatically transitions between the two modes. The
converter operates as a PWM when a synchronization signal is present
at the sync input. The converter operates as a linear regulator in the
absence of a synchronization signal. The PWM mode offers excellent
performance at normal to heavy loads at the sacrifice of output ripple
voltage. The linear mode offers excellent noise rejection at the
sacrifice of system efficiency. The user is able to select which mode
will give the best performance for a given operating condition.
Internal protection features include thermal shutdown with hysteresis
and cycle−by−cycle current limit in the PWM mode. Additionally, the
converter transitions into PFM mode at very light loads if a
synchronization signal is present and an output overvoltage condition
is detected.
PWM Features
• Current Mode Control with Cycle−by−Cycle Current Limit
• Nominal Synchronization Frequency of 270 to 630 kHz
• Built−in Slope Compensation
Linear Regulator Features
• Low Output Noise
Overall Features
• Thermal Shutdown with Hysteresis
• Digitally Programmable Output Voltage Between 4 Voltages:
1.0, 1.3, 1.5, and 1.8
• Fast Transient Response
• Input Voltage Range From 2.7 V to 5.4 V
• Space Saving Micro8 Package
• Low Shutdown Current of 0.18 mA Typical
• Pb−Free Package is Available
Typical Applications
• Baseband Supplies for Portable Handsets
• PDAs
• Supplies for DSP Circuitry
L
C_OUT
1 SHD
2 SYN
3 V_O
4 LX
MBRM120
CB0 8
CB1 7
GND 6
V_IN 5
C_IN
V_IN
L = 15 mH
C_IN = 10 mF
C_OUT = 10 mF
Figure 1. Typical Operating Circuit
© Semiconductor Components Industries, LLC, 2004
1
February, 2004 − Rev. 4
http://onsemi.com
8
1
MARKING
DIAGRAM
Micro8t
(MSOP−8)
DM SUFFIX
CASE 846A
8
1500
AYW
1
A = Assembly Location
Y = Year
W = Work Week
PIN CONNECTIONS
SHD 1
SYN 2
V_O 3
LX 4
(Top View)
8 CB0
7 CB1
6 GND
5 VIN
ORDERING INFORMATION
Device
Package
Shipping^†
NCP1500DMR2
Micro8
4000 Tape/Reel
NCP1500DMR2G Micro8
(Pb−Free)
4000 Tape/Reel
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specifications
Brochure, BRD8011/D.
Publication Order Number:
NCP1500/D