AP3102/V/L

Document number: DS37419 Rev.2 - 2

10 of 14

www.diodes.com

July 2014

© Diodes Incorporated

AP3102/V/L

A Product Line of

Diodes Incorporated

the standby power and audible noise for most applications.

Another function of ADJ pin is to use it as the latch trigger input. When the voltage at this pin is more than 4.5V, the system will be latched by

decreases to a very low value just like unplugged the AC input. Then, the IC latch current can't be maintained and latch will be released (see

description below). This function can be used as system OTP and other protection.

System Protection and Pin Fault Protection

AP3102/V/L provides versatile system and pin fault protections. The OCP comparator realizes the cycle-by-cycle current limiting (OCP).

Cooperating with BOK compensation from the input line voltage, the IC realizes the constant over load protection (OLP). VCC over voltage

protection can be applied as the primary OVP or opto-coupler broken protection. The AP3102/V/L also has pin fault connection protection

including floating and short connection. The floating pin protection includes the RI, SENSE, FB, etc; the short pin protection includes the RI pin

short protection. When these pins are floated or RI pin is shorted to ground, PWM switching will be disabled, thus protect the power system. Below

figures show the relative timing sequences of system protections.

Gate drive

UVLO

4V

0.5V

35mS

35mS

4.2V

Line OVP & Brown-Out

Output Short

Vo

VCC OVP (AP3102)

25

S

28V

Gate

drive

Latch until unplug AC

UVLO

>25

S

4V

De-latch Point

Auto Recoverable Protection Mode

Latch Protection Mode

35mS

4.2V

Vo

Latch through ADJ Pin

Output Short (AP3102L)

VCC OVP

(AP3102V, AP3102L)

25

S

28V

UVLO

25

S

Typical Timing Sequences of AP3102/V/L Protections