TX5121 General Description:
The TX5121 is a step-up DC/DC converter specifically designed to drive up to 5 series white LEDs with constant current. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminates the need for ballast resistors.
The TX5121 switches at 1.4MHz, allowing the use of tiny external components. A low 0.25V feedback voltage minimizes power loss in the current setting resistor for high efficiency. The OVP pin monitors the output voltage and turns off the converter whenever the LEDs are open.
The TX5121 switches at 1.4MHz, allowing the use of tiny external components. A low 0.25V feedback voltage minimizes power loss in the current setting resistor for high efficiency. The OVP pin monitors the output voltage and turns off the converter whenever the LEDs are open.
The TX5121 is available in low profile SOT-23-6 package.
TX5121 Features:
Inherently Matched LED Current
High Efficiency:82%
Drives Up to Five LEDs from 2.2V Supply
17V Over Voltage Protection
Fast 1.4MHz Switching Frequency
Requires Only 1μF Output Capacitors
SOT-23-6 Package
TX5121Applications:
Communication equipment
White LED Backlight Display for PDA
Pocket PC
Handheld Devices
Cellular Phones
White LED display backlighting
TX5121 Block Diagram:
TX5121 Pin Assignment:
TX5121 Order Information:
TX5121①②
Designator
|
Symbol
|
Description
|
①
|
M
|
Package:SOT23-6
|
②
|
R
|
RoHS / Pb Free
|
G
|
Halogen Free
|
TX5121 Typical Application Circuit: