High Input Voltage Step-Down Switching Regulator

5/19/2003 Edited byPETech Staff High Input Voltage Step-Down Switching Regulator Linear Technology’s new LT3431 is a high-voltage constant frequency step-down switching regulator that uses a 3A internal switch. It operates within a VIN range of 5.5V to 60V, and delivers up to 2.75A of continuous output current at voltages as low as 1.25V, making it ideal for telecom, automotive, and industrial applications. Its unique high-voltage architecture enables efficiencies as high as 90% even in low duty cycle applications.

The LT34301 uses a constant 500 kHz switching frequency, keeping external components small. A sync pin allows for external synchronization from 580 kHz to 700 kHz with logic level inputs. It comes in a thermally enhanced TSSOP package that optimizes heat dissipation within a very small, low profile circuit footprint.

The LT3431 utilizes a high efficiency 3A, 0.1Ω switch, with the necessary oscillator, control, and logic circuitry integrated into a single die. Special design techniques and a new high voltage process enable high efficiency over a wide input voltage range while its current mode topology enables fast transient response and excellent loop stability. Patented circuitry maintains peak switch current over the entire duty cycle range. Supply current is only 2.5mA during normal operation, while shutdown current is reduced to 30uA.

For more information, visit www.linear.com.