SC623AEVB datasheet(13/21 Pages) SEMTECH

13 / 21 page

SC623A

Over-Temperature Protection

The Over-Temperature (OT) protection circuit helps

prevent the device from overheating and experiencing

a catastrophic failure. When the junction temperature

exceeds 160°C, the device goes into thermal shutdown

with all outputs disabled until the junction temperature

is reduced. All register information is retained during

thermal shutdown.

Charge Pump Output Current Limit

The device also limits the charge pump current at the

VOUT pin. When VOUT is shorted to ground, the typical

output current is 300mA. The current limiting is triggered

by an output under-voltage lockout below 2V. The output

returns to normal when the short is removed and VOUT is

above 2.5V. Above 2.5V, a typical current limit of 300mA

applies when the FL current sink is off and a typical current

limit of 1A applies when the FL current sink is on.

Applications Information (continued)

LED Float Detection

Float detect is a fault detection feature of the LED current

sink outputs. If an output is programmed to be enabled

and an open circuit fault occurs at any current sink output,

that output will be disabled to prevent a sustained output

OVP condition from occurring due to the resulting open

loop. Float detect ensures device protection but does

not ensure optimum performance. Unused LED outputs

must be disabled to prevent an open circuit fault from

occurring.

SC623AEVB Datasheet(PDF) 13 Page - Semtech Corporation