Texas Instruments LMR62421 Boost/SEPIC Regulator 2.7-5.5V In 3-24V Out 2.1A

The Texas Instruments LMR62421 Boost/SEPIC Regulator is a monolithic step-up voltage regulator that delivers up to 2.1A of output current from a 2.7V to 5.5V input.

Part of the SIMPLE SWITCHER family, this compact component is designed for both Boost and SEPIC topologies. It integrates all active functions required for efficient local DC/DC conversion, offering fast transient response and accurate regulation while minimising PCB footprint.

Overview

Operating at a switching frequency of 1.6MHz, the regulator allows the use of extremely small surface-mount inductors and ceramic capacitors, which helps reduce the size of the external bill of materials. Current-mode control and internal compensation simplify design, reduce component count, and support stable operation across a wide range of input voltages and load conditions.

Key Features

• Adjustable output voltage from 3V up to 24V
• Wide input voltage range of 2.7V to 5.5V
• Output current of up to 2.1A
• Efficiency of up to 90%, typically around 83%
• Fixed switching frequency of 1.6MHz
• External shutdown with an ultra-low standby current of 80nA
• Internal soft-start to limit inrush current
• Cycle-by-cycle current limiting for overload protection
• Thermal shutdown to safeguard the IC under fault conditions

Applications

The external shutdown feature and low standby current are intended for portable applications, where battery life is a consideration. The regulator is also suited to power-sensitive designs requiring compact, efficient local DC/DC conversion.

Physical Details

The unit has a weight of 0.907 g, with dimensions of 3.3 (width) x 1.5 (depth) x 4.3 (height). Its integrated design reduces external component requirements and PCB footprint, making it a practical option for compact Boost and SEPIC power designs.