General Description

The EC4503 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 identical 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 EC4503 also integrates under-voltage lockout, Overtemperature protection, and current limit circuits to Protect the IC in abnormal conditions.
The EC4503 is available in a SOT-23-6 packages.

Features

●Wide Input Voltage from 2.7V to 6V
●0.2V Reference Voltage
●Fixed 1.5MHz Switching Frequency
●PWM Brightness Control with Wide Frequency Range of 100Hzto 100kHz
●Build‐In Power MOSFET : 0.2Ω
●Open‐LED Protection
●Under‐Voltage Lockout Protection
●Over‐Temperature Protection
●<1mA Quiescent Current during Shutdown
●SOT‐ 23‐ 6 Packages
● Lead Free and Green Devices Available
●(RoHS Compliant)

Applications

●White LED Display Backlighting
●Cell Phone and Smart Phone
●PDA, PMP, MP3
●Digital Camera