Features

• Wide Input Voltage Range: 4.5V to 100V
• Ultralow Quiescent Current and Low Ripple Burst Mode® Operation: I_Q = 6μA
• 0.5A, 140V Power Switch
• Positive or Negative Output Voltage Programming with a Single Feedback Pin
• Programmable Frequency (100kHz to 500kHz)
• Synchronizable to an External Clock
• BIAS Pin for Higher Efficiency
• Programmable Undervoltage Lockout (UVLO)
• Thermally-Enhanced High Voltage MSOP Package

Typical Application

Description

The LT®8331 is a current mode DC/DC converter with a 140V, 0.5A switch operating from a 4.5V to 100V input. With a unique single feedback pin architecture, it is capable of boost, SEPIC, flyback or inverting configurations. Burst Mode operation consumes as low as 6μA quiescent current to maintain high efficiency at very low output currents, while keeping typical output ripple below 20mV.

The internally-compensated current mode architecture results in stable operation over a wide range of input and output voltages and programmable switching frequencies between 100kHz to 500kHz. A SYNC/MODE pin allows synchronization to an external clock. It can also be used to select between burst or pulse-skipping modes of operation. For increased efficiency, a BIAS pin can accept a second input to supply the INTV_CC regulator. Additional features include frequency foldback and programmable soft-start for controlling inductor current during start-up.

The LT8331 is available in a thermally-enhanced MSOP package with four pins removed for high voltage spacings.