NCP5030
Buck−Boost Converter
to Drive a Single LED from 1
Li−Ion or 3 Alkaline
Batteries
The NCP5030 is a fixed frequency PWM buck−boost converter
optimized for constant current applications such as driving
high−powered white LED. The buck−boost is implemented in an
H−bridge topology and has an adaptive architecture where it operates
in one of three modes: boost, buck−boost, or buck depending on the
input and output voltage condition. This device has been designed
with high−efficiency for use in portable applications and is capable
of driving in DC up to 900 mA into a high power LED for flashlight /
torch applications. To protect the device cycle−by−cycle current
limiting and a thermal shutdown circuit have been incorporated as
well as output over−voltage protection. The 700 kHz switching
frequency allows the use of a low value 4.7 mH and ceramic
capacitors. The NCP5030 is housed in a low profile space efficient
3x4 mm thermally enhanced WDFN.
http://onsemi.com
12
MARKING
DIAGRAM
1
1
WDFN12 3x4
MT SUFFIX
CASE 506AY
5030
ALYWG
G
5030
= Specific Device Code
= Assembly Location
= Wafer Lot
= Year
= Work Week
A
L
Y
W
G
Features
= Pb−Free Package
• Efficiency: 87% at 500 mA and 3.3 V V
IN
(Note: Microdot may be in either location)
• Internal Synchronous Rectifier, No Schottky Diodes
• Adjustable Switching Limit Current to Optimize inductor size
• 0.3 mA Shut−down Control with “True−Cut off”
• Input Voltage Range from 2.7 V to 5.5 V
PIN CONNECTIONS
• 200 mV Feedback Voltage
FB
COMP
CTRL
1
2
3
12
11 AGND
PCA
• Output Over−voltage and Thermal Shut Down Protection
Typical Applications
• Portable Flashlight / Torch Lights
VIN
10
13
VS
PVIN
C2
10 mF
Vin
4
5
6
9
8
7
4.7 mH
VOUT
LX2
LX1
LX1
1 Cell
Li−Ion
Cin
1 mF
L1
C
in
2.7 to 5.5
C3
22 mF
(Top View)
39 k
PCA
VOUT
VS
D1
Exposed pad (Pin 13) is PGND
must be soldered to PCB GND plane
R1
ENABLE
CTRL
C
out
NCP5030
ORDERING INFORMATION
See detailed ordering and shipping information in the package
L1: TDK RLF7030T−4R7M3R4
C1: 1 mF 6.3 V X5R
C2: 10 mF 3.6 V 0805
TDK: C2012X5R0J106MT
C3: 22 mF 6.3 V X5R
TDK: C2012X5R0J226MTJ
dimensions section on page 13 of this data sheet.
R3
220 m
R2
100 k
C4
22 pF
R
C5
330 pF
SENSE
Figure 1. Typical Application Circuit
©
Semiconductor Components Industries, LLC, 2006
1
Publication Order Number:
December, 2006 − Rev. 0
NCP5030/D