Fremont Micro Devices

FT833xxx

© 2013 Fremont Micro Devices Inc.

Confidential Rev1.1

DS833xxx-A-page9

and charged up again, the system works in a hiccup mode.

LED Short Circuit Protection

When LED short circuit is detected, the system works at minimum frequency (Fop=5KHz), so the power

consumption is low.

CS Resistor Short or Transformer Saturation

In these catastrophic fault conditions, the internal fast fault detection circuit will trigger and latch, the system

stops switching immediately. VCC will be pulled down and charged up again, the system works in a hiccup

mode.

Over Temperature Compensation

FT833xxx senses the die temperature after start up, and the thermal compensation threshold is set to 150℃

with a 25

hysteresis. When

℃

FT833xxx temperature rises and reaches the threshold, the output current will

be reduced by half until the IC temperature falls 25℃ below the thermal compensation trigger point, at which

point the output current will recover to 100% of its designed target.