This document provides detailed information on the design decisions made for a converter and describes methods for modifying the design for various applications. The document describes the design of an isolated version of the converter and the VCC power start-up method. It also explains how to program the output voltage by adjusting resistor values and how to select the frequency.
This document details the design decisions made when creating a flyback DC/DC converter using the LTC3805 controller. It describes methods for altering the design for various applications, including isolated versions. The text covers power and start-up configurations, output voltage programming, and frequency selection.
| Shutdown Current | 40µA |
|---|---|
| VCC Falling Threshold | 4V |
| RUN Pin Rising Threshold | 1.2V |
| Synchronization Lock-on Time | two cycles |
| Synchronization Recovery Time | two cycles |
The rate of change of VOUT at start-up is programmed by the capacitor on the SSFLT pin.
The overcurrent protection level is set by a resistor in series with the OC pin using a constant 10µA current sourced by the OC pin.