APW7236 Datasheet, PDF (1/17 Pages) Anpec Electronics Coropration – 1.5MHz Step-Up Converter for White LEDs

APW7236
1.5MHz Step-Up Converter for White LEDs
Features
General Description
• Wide Input Voltage from 2.7V to 6V
• Fixed 1.5MHz Switching Frequency
• Reference Voltage : 0.2V
• PWM Brightness Control with Wide Frequency
Range of 100Hz to 100kHz
• Build-In Power MOSFET : 0.2Ω
• Open-LED Protection
• Under-Voltage Lockout Protection
• Over-Temperature Protection
• <1µA Quiescent Current during Shutdown
• TSOT-23-6A and TDFN2x2-8 Package
• Halogen and Lead Free Available
(RoHS Compliant)
Applications
The APW7236 is a current-mode and fixed frequency
boost converter with an integrated N-FET to drive white
LEDs.
The series connection allows the LED current to be iden-
tical for uniform brightness. Its low on-resistance of NFET
and low feedback voltage reduce power loss and achieve
high efficiency. Fast switching frequency(1.5MHz typical)
allows using small-size inductor and both of input and
output capacitors. An over voltage protection function,
which monitors the output voltage via OVP pin, stops
switching of the IC if the OVP voltage exceeds the over
voltage threshold. An internal soft-start circuit eliminates
the inrush current during start-up.
The APW7236 also integrates under-voltage lockout, over-
temperature protection, and current limit circuits to pro-
tect the IC in abnormal conditions. The APW7236 is avail-
able in a TSOT-23-6A and TDFN2x2-8 package.
• White LED Display Backlighting
• Cell Phone and Smart Phone
• PDA, PMP, MP3
• Digital Camera
Simplified Application Circuit
Pin Configuration
TSOT-23-6A
Top View
LX 1
GND 2
FB 3
6 VIN
5 OVP
4 EN
VIN
C1
4.7µF
OFF ON
L1
4.7µH
VIN
LX
GND
OVP
EN
FB
I_LED
VOUT
C2
µF
7~9 strings
R1
TDFN2x2-8
(Top View)
GND 1
VIN 2
OVP 3
EN 4
GND
8 LX
7 NC
6 FB
5 GND
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.4 - Sep., 2012
www.anpec.com.tw