AL3022

Document number: DS36514 Rev. 3 - 2

8 of 12

www.diodes.com

September 2014

© Diodes Incorporated

AL3022

3043

A Product Line of

Diodes Incorporated

AL3022

FB

EN

R

DC Voltage

0.8V to 2.4V

Figure 2. Analog Dimming Control Using a DC Voltage Signal in EN Pin

Soft Start Control

The AL3022 external compensation circuit can clamp the output waveform to soft start smoothly.

Operation Protection

1. Under Voltage Lockout

The AL3022 provides an under voltage lockout circuit to prevent it from undefined status when startup. The Under Voltage Lockout circuit turns the

rises to 3.8V.

2. Over Voltage Protection / LED Open Protection

The controller has an internal OVP circuit. The controller output voltage will boost too high when LEDs are disconnected from the circuit or fail to

open. The AL3022 will latch off the output if the OVP pin senses a voltage that is larger than 1.55V, and the power switching will be turned off. The

latched off status can be reset by reducing the supply voltage to lower than 3.6V or EN lower than 0.3V.

The AL3022 monitors the OVP pin, if the OVP pin voltage is less than 0.1V, MOSFET drive output will turn off. When OVP is higher than 0.1V,

4. Over Current Protection

The AL3022 integrates an OCP circuit. The CS pin is connected to the voltage-sensor (RCS) that placed between the Drain of MOS and GND. If

the voltage on CS pin exceeds 0.33V, it is turned off immediately and will not turn on until the next cycle begins.

5. Over Temperature Protection

The AL3022 monitors the temperature of itself. The AL3022 shuts itself off if the temperature exceeds the threshold value (typically +160

a no-latched protection. The device recovers once the temperature has decreased approximately +20