［AP2152］

MS1348-E-00

4

2012/05

Pin No.

Pin Name

Function

12

RT

Switching frequency set pin. Oscillation frequency can be set by connecting a resistor

between the RT pin and GND. Please refer to section 2.4 “Switching frequency

setting/Function of synchronizing with external clock”.

13

ISET

LED driving current set pin. LED current can be set by connecting a resistor between the

ISET pin and GND. Please refer to section 2.3 “LED current setting”.

14

TM

Capacitor connection pin for timer. If an abnormality occurs in the IC, this pin outputs

10µA constant current. If this pin voltage exceeds 2.0V, the IC ceases its operation. By

returning to the standby state, the timer is reset and the IC can be released. When the

timer is unnecessary, please connect to GND. Please refer to section 2.6 “Timer latch (TM)

setting”.

15

PGOOD

Power Good pin. N channel open-drain, it keeps OFF when normal operation. If an

abnormality occurs in the IC, the operation is latched off by timer latch function and

internal FET turns ON. Please refer to “Protections description” for the detail of Power

Good pin status described later. When the power good function is unnecessary, please

connect to GND.

16

NC

NC pin.

17

CH3

WLEDs constant current circuit 3. CH3 is open drain, and provides constant current to the

LEDs. If this constant current channel is unnecessary, please keep this pin open.

18

CH2

WLEDs constant current circuit 2. CH2 is open drain, and provides constant current to

LEDs. If this constant current channel is unnecessary, please keep this pin open.

19

CH1

WLEDs constant current circuit 1. CH1 is open drain, and provides constant current to

LEDs. If this constant current channel is unnecessary, please keep this pin open.

20

GND

GND pin for internal circuits.

-

THERMAL

PAD

For heat radiation, connection to GND is recommended.

This is electrically isolated from the internal circuit.

ABSOLUTE MAXIMUM RATINGS

Rating

Symbol

Value

Unit

Condition

VIN voltage

-0.3 to +45

V

*1

LX, CH1-3 Voltage

-0.3 to +45

V

*1

SDATA, SCLK, PWM,VDC,

PGOOD, SYNC voltage

-

-0.3 to +6

V

*1

OVP, COMP, RT,

ISET, TM, CLKO voltage

-

V

*1*4

CH1-3 current

140

mA

PGOOD current

20

mA

Power Dissipation

2500

mW

*2, *3

Operating Temperature Range

-40 ~ +105

°

C

Storage Temperature Range

-55 ~ +150

°

C

Note:

*1. All voltages refer to GND pin (GND, PGND) as zero (reference) voltage.

*2. PD must be decreased at the rate of 23.3mW/°C for operation above 25°C.

*3. Mounted on a 50 mm × 50 mm x 1 mm double sided FR-4 board.

Note：The maximum ratings are the absolute limitation values with the possibility of damage/breakage.

When operation exceeds this standard, quality cannot be guaranteed.