MP1521

·On Board Power MOSFET
·Drive 9 White LEDs from 2.7V Input
·Drive 15 White LEDs from 5V Input
·Up to 90% Efficiency
·Over 80mA Output Current Capacity
·Open Load Shutdown
·Low Current Sensing Feedback Voltage
·Up to 3 String Current Sensing Feedback
·Analog and Digital PWM Brightness Control
·UVLO, Thermal Shutdown
·Soft Start
· Internal Current Limit
·Available in Compact MSOP10 and Tiny 3 mm x 3 mm QFN16 Package
·Evaluation Boards Available

The MP1521 is a constant-current Boost Regulator. This IC has three individual current-sensing feedbacks, which are ideal for driving multiple strings of series connected LEDs. The OLS pin is designed for detecting loose or open LED connections.

The MP1521 uses a peak current, constant minimum off-time architecture. The feedback pins measure voltage across sense resistors in series with the LED strings. When supplying a bias current of 20mA, the voltage drop across the sense resistor is only 0.4V to minimize power loss. Either a DC voltage or a PWM signal at the BRT/PWM input can control the LED brightness.

The MP1521 has an on board power MOSFET switch that is protected by current limit, open load shutdown, thermal shutdown, and undervoltage lockout.