NCP1509
Up to 500 mA, 1 MHz, High
Efficiency Synchronous
Step−Down DC−DC
Converter in DFN Package
http://onsemi.com
The NCP1509 step−down PWM DC−DC converter is optimized for
portable applications powered from 1−cell Li−ion or 3 cell
Alkaline/NiCd/NiMH batteries. This DC−DC converter utilizes a
current−mode control architecture for easy compensation and better
line regulation. It also uses synchronous rectification to increase
efficiency and reduce external part count. The NCP1509 optimizes
efficiency in light load conditions when switched from a normal PWM
mode to a “pulsed switching” mode. The device also has a built−in 1
MHz (nominal) oscillator for the PWM circuitry, or it can be
synchronized to an external 500 kHz to 1000 kHz clock signal. Finally,
it includes an integrated soft−start, cycle−by−cycle current limiting,
and thermal shutdown protection. The NCP1509 is available in a space
saving, low profile 3x3 mm 10 pin DFN package.
MARKING
DIAGRAM
1
10 PIN DFN
MN SUFFIX
CASE 485C
1509
ALYW
1
1509 = Specific Device Code
A
L
Y
W
= Assembly Location
= Wafer Lot
= Year
= Work Week
Features
• High Efficiency:
92.5% for 1.8 V Output at 3.6 V Input and 125 mA Load Current
91% for 1.8 V Output at 3.6 V Input and 300 mA Load Current
ORDERING INFORMATION
Device
Package
Shipping†
• Digital Programmable Output Voltages: 1.05, 1.35, 1.57 or 1.8 V
• Output Current up to 500 mA at V = 3.6 V
in
3000 Tape & Reel
NCP1509MNR2
10 Pin DFN
• Low Quiescent Current of 14 mA in Pulsed Switching Mode
• Low 0.2 mA Shutdown Current
NCP1509MNR2G 10 Pin DFN 3000 Tape & Reel
(Pb−Free)
• −30°C to 85°C Operation Temperature
• Low Profile DFN Package
• Pb−Free Package is Available
†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.
Application
• Cellular Phones, Smart Phones and PDAs
• Digital Still Cameras
• MP3 Players and Portable Audio Systems
100
• Wireless and DSL Modems
90
• Portable Equipment
80
Pulsed Mode
PWM Mode
6.8 mH
70
60
50
40
30
20
10
V
5
4
3
6
in
VCC
LX
V
out
2.7 V − 5.2 V
C
VCCP
C
out
22 mH
in
10 mH
FB
9
SHD
8
7
CB1
CB0 and CB1
Control Input
10
SYNC CB0
V
in
= 3.6 V
GNDA GNDP
V
out
= 1.8 V
0
0.001
0.01
0.1
1
10
100
1000
I
(mA)
out
Figure 1. Typical Application Circuit
Figure 2. Efficiency vs. Output Current
© Semiconductor Components Industries, LLC, 2006
1
Publication Order Number:
July, 2006 − Rev. 1
NCP1509/D