AL3065 datasheet(11/15 Pages) DIODES

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AL3065

Document number: DS37677 Rev. 1 - 2

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www.diodes.com

April 2015

AL3065

Application Information (Cont.)

2) Over-Current Protection

The AL3065 integrates an OCP circuit. The CS pin is connected to the voltage-sensor (RCS) placed between the source of the MOSFET and

GND. If the voltage at CS pin exceeds 0.54V, the MOSFET is turned off immediately and will not turn on until the next cycle begins.

3) LED Short-Circuit Protection

The AL3065 integrates an LED Short-Circuit Protection circuit. If the voltage at any of the CH1 to CH4 pins exceeds a threshold of approximately

7.3V during normal operation, the corresponding channel is latched off. Toggle VIN or EN to reset the latch. LED short detecting logic priority is

lower than open LED and OVP logic. The LED short detecting is triggered when 0.1V < VLED_MIN under dimming on mode, and disabled when

LED open occurs until output voltage resumes to the regulated voltage.

4) LED Open-Circuit Protection

The AL3065 integrates an LED Open-Circuit Protection circuit. When any LED string is open, VOUT will boost up until the voltage at OVP pin

reaches an approximate threshold of 2.0V. The IC will automatically ignore the open string whose corresponding pin voltage is less than 100mV

and the remaining string will continue operation. If all the strings are open and the voltage at OVP pin reaches a threshold of 2.0V, the MOSFET

drive gate will turn off and the IC will shut down and latch.

5) VOUT Short/Open Schottky Diode Protection

The AL3065 monitors the OVP pin, if the OVP pin voltage is less than 0.1V, MOSFET drive output will turn off. This protects the converter if the

output Schottky diode is open or VOUT is shorted to ground.

6) Under-Voltage Lockout

The AL3065 provides an under voltage lockout circuit to prevent it from undefined status when it starts up. The UVLO circuit shuts down the

device when VCC drops below 3.8V. The UVLO circuit has 200mV hysteresis, which means the device starts up again when VCC rises to 4.0V.

7) Over-Temperature Protection

The AL3065 features Over-Temperature Protection. If the junction temperature exceeds approximately +160ºC, the IC will shut down until the

junction temperature is less than approximately +140ºC. When the IC is released from over temperature shutdown, it will start a soft-start process.

8) Schottky Diode/Inductor Short-Circuit Protection

The AL3065 features Schottky Diode/Inductor Short-Circuit protection circuit. When CS pin voltage exceeds 0.8V for greater than 16 switching

clocks, the IC will latch off. The voltage of CS pin is monitored after a short delay of tLEB.

9) Shut Down under Abnormal Condition

The AL3065 features Shutdown under Abnormal Condition Protection circuit. When the OVP pin voltage exceeds 3.2V, the IC will latch off. Toggle

EN pin to restart the IC. This feature can be used to shut down the IC under any defined abnormal condition.

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