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FAN73402 • 1.0.0

3

Pin Assignments

Figure 2. Package Diagram

Pin Definitions

Pin #

Name

Description

1

VCC

This pin is the supply voltage of the IC.

2

DRV

This pin is the gate drive signal of the boost switch.

3

GND

This pin is the ground of the IC.

4

CS

This pin is for sensing the current flowing through an external MOSFET. It includes a built-in

300ns blanking time. The peak of the current flowing through the MOSFET is limited to this

pin voltage. Slope compensation of the boost controller can be programmed through the

series resistor of this pin.

5

REF

This pin is the 5V reference voltage pin. Maximum current capability is 3mA.

6

FAULT

This pin is for indicating the fault signal. This pin is connected to the open drain. When OLP

protection is occurred, the FAULT pin is pulled HIGH.

7

RT

Oscillator frequency set of the boost switch (50kHz ~ 300kHz).

8

SENSE

This pin is for sensing the current flowing through the LEDs. A sensing resistor is connected

from this pin to ground. This pin is connected to the negative input of the internal error

amplifier.

9, 10

DRAIN

Drain pin of PWM dimming power MOSFET.

12

ENA

Enable input pin. If voltage of this pin is higher than 1.22V, the IC starts to operate. If the

voltage of this pin is lower than 1.15V, the IC stops operating.

13

OVP

Over-voltage protection input pin. Output voltage of the boost circuit is connected to this pin

through a resistor divider circuit. If this pin voltage is higher than 3V, OVP is triggered.

14

CMP

This pin is the error amplifier output. Typically, a compensation capacitor and resistor are

connected to this pin from the ground.

15

ADIM

This pin is for setting the current flowing through the LEDs. This pin is connected to the

positive inputs of the internal error amplifier. Linear voltage range of ADIM is 0.3V~3.0V.

16

BDIM

This pin is for the burst dimming signal. If this pin voltage is HIGH, the internal dimming

MOSFET is turned on. If this pin voltage is LOW, the dimming MOSFET is turned off.

Note:

1. Pin 11 is a “No Connect” pin (not shown in Figure 2).