APW7136A Datasheet, PDF (1/15 Pages) Anpec Electronics Coropration – 1MHz, High-Efficiency, Step-Up Converter for 2 to 8 White LEDs

APW7136A/B/C
1MHz, High-Efficiency, Step-Up Converter for 2 to 8 White LEDs
Features
• Wide Input Voltage from 2.7V to 6V
• 0.25V Reference Voltage
• Fixed 1MHz Switching Frequency
• High Efficiency up to 87%
• 100Hz to 100KHz PWM brightness control fre-
quency
• Open-LED Protection
• Under Voltage Lockout Protection
• Over Temperature Protection
• <1µA Quiescent Current during Shutdown
• SOT-23-6 Package
• Lead Free Available (RoHS Compliant)
Applications
• White LED Display Backlighting
• Cell Phone and Smart Phone
• PDA, PMP, MP3
• Digital Camera
Pin Configuration
SOT-23-6 Top View
LX 1
GND 2
FB 3
6 VIN
5 OVP
4 EN
General Description
The APW7136A/B/C is a current-mode and fixed frequency
boost converter with an integrated N-FET to drive up to 8
white LEDs in series.
The series connection allows the LED current to be iden-
tical for uniform brightness. Its low on-resistance of N-
FET and feedback voltage reduce power loss and achieves
high efficiency. Fast 1MHz current-mode PWM operation
is available for input and output capacitors and a small
inductor while minimizing ripple on the input supply. The
OVP pin monitors the output voltage and stop switching if
exceeds the over-voltage threshold. An internal soft-start
circuit eliminates the inrush current during start-up.
The APW7136A/B/C also integrates under-voltage
lockout, over-temperature protection and current limit
circuits. The APW7136/A/B/C is available in a SOT-23-6
package.
Simplified Application Circuit
V_IN
C1
4.7µF
OFF ON
L1
22µH
6 _VIN
LX ¹
2
GND
OVP ⁵
4
EN
FB ³
V_OUT
C2
1µF _{Up to 8}
WLEDs
R1
12Ω
Ordering and Marking Information
Note: ANPEC lead-free products contain molding compounds/die attach materials and 100% matte tin plate termination finish; which are fully
compliant with RoHS and compatible with both SnPb and lead-free soldering operations. ANPEC lead-free products meet or exceed the lead-
free requirements of IPC/JEDEC J STD-020C for MSL classification at lead-free peak reflow temperature.
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and
advise customers to obtain the latest version of relevant information to verify before placing orders.
Copyright © ANPEC Electronics Corp.
1
Rev. A.2 - Jan., 2008
www.anpec.com.tw