General Description

The LP3321 is a 1.0MHz PWM boost switching regulator designed for constant-current white LED driver applications.The LP3321 can drive a string of up to 11 white LEDs in series,ensuring uniform brightness and eliminating several ballast resistors.

The LP3321 implements a constant frequency 1.0MHz PWM control scheme.The high frequency PWM operation also saves board space by reducing external component sizes.To improve efficiency,the feedback voltage is set to 200mV,which reduces the power dissipation in the current setting resistor.Highly integration and internal compensation network minimizes as 5 external component counts.Optimized operation frequency can meet the requirement of small LC filters value and low operation current with high efficiency.

Features

Up to 94%efficiency

Shut-down current:<1uA

Output voltage Up to 37V

Internal Compensation,Soft-start

Support down to 1%Dimming Duty Cycle

1.0MHz fixed frequency switching

High switch on current:1.5A

Available in SOT23-6&TDFN-6(2mm×2mm)