ZLED7x20 Datasheet

© 2016 Integrated Device Technology, Inc.

14

April 20, 2016

2.8

ZLED7x20 Protection Features

2.8.1

Thermal Shut-down Protection

The ZLED7x20 automatically protects itself from damage due to over-temperature conditions. If the ZLED7x20’s

temperature exceeds the thermal shutdown threshold (TSD = 150°C, typical), the ZLED7x20 will shut down. To

avoid erratic ZLED7x20 operation, a 20K hysteresis (TSD-HYS) is applied that prevents it from returning to operation

until its temperature falls below the hysteresis threshold (TSD - TSD-HYS). Also refer to section 3.2 for additional

thermal considerations.

2.8.2

LED Open Load Protection

As a step-down converter, the ZLED7x20 has inherent open-load circuit protection. Since the L1 inductor is

connected in series with the LED string, the current flow is interrupted if the load is open and the LX output of the

ZLED7x20 will not be damaged. This provides an advantage over other products such as boost converters, for

which the internal switch can be damaged by back EMF forcing the drain above its breakdown voltage.