Features

• Input Voltage Range: 6V to 100V
• Duty Mode Control Regulates an Isolated Output without an Opto
• High Efficiency Synchronous Control
• Short-Circuit (Hiccup Mode) Overcurrent Protection
• Programmable OVLO and UVLO with Hysteresis
• Programmable Frequency (100kHz to 500kHz)
• Synchronizable to an External Clock
• Positive or Negative Polarity Output Voltage Feedback with a Single FBX Pin
• Programmable Soft-Start
• Low Shutdown Current < 1μA
• Available in FE20 TSSOP with HV Pin Spacing

Typical Application

Description

The LT®8310 is a simple-to-use resonant reset forward converter controller that drives the gate of a low side N-channel MOSFET from an internally regulated 10V supply. The LT8310 features duty mode control that generates a stable, regulated, isolated output using a single power transformer. With the addition of output voltage feedback, via opto-coupler (isolated) or directly wired (nonisolated), current mode regulation is activated, improving output accuracy and load response. The flexibility to choose transformer turns ratio makes high step-down or step-up ratios possible without operating at duty cycle extremes.

The user can program the switching frequency from 100kHz to 500kHz to optimize efficiency, performance or external component size. A synchronous output is available for controlling secondary side synchronous rectification to improve efficiency. User programmable protection features include monitors on input voltage (UVLO and OVLO) and switch current (overcurrent limit). The LT8310 soft-start feature helps protect the transformer from flux saturation.