CAT3604V

http://onsemi.com

9

Table 6. PIN DESCRIPTION

Pin #

Name

Function

1

EN

Device enable (active high).

2

NC

Not connected inside the package.

3

NC

Not connected inside the package.

4

NC

Not connected inside the package.

5

RSET

Connect resistor RSET to set the LED current.

6

VOUT

Charge pump output connected to the LED anodes.

7

VIN

Charge pump input, connect to battery or supply.

8

C1+

Bucket capacitor 1 Positive terminal

9

C1−

Bucket capacitor 1 Negative terminal

10

C2−

Bucket capacitor 2 Negative terminal

11

C2+

Bucket capacitor 2 Positive terminal

12

GND

Ground Reference

13

LED4

LED4 cathode terminal.

14

LED3

LED3 cathode terminal.

15

LED2

LED2 cathode terminal.

16

LED1

LED1 cathode terminal.

TAB

GND

Connect to GND on the PCB.

Pin Function

VIN is the supply pin for the charge pump. A small 1

mF

ceramic bypass capacitor is required between the VIN pin

and ground near the device. The operating input voltage

range is from 2.5 V to 5.5 V. Whenever the input supply falls

below the under−voltage threshold (1.8 V), all the LED

channels are disabled and the device enters shutdown mode.

EN is the enable input and the high resolution PWM

dimming control. Levels of logic high and logic low are set

at 1.3 V and 0.4 V respectively. When EN is initially taken

high, the device becomes enabled and all LED currents are

“zero current” shutdown mode, the EN pin must be held low

for at least 1.5 ms.

VOUT is the charge pump output that is connected to the

LED anodes. A small 1

mF ceramic bypass capacitor is

GND is the ground reference for the charge pump. The pin

must be connected to the ground plane on the PCB.

C1+, C1− are connected to each side of the ceramic bucket

C2+, C2− are connected to each side of the ceramic bucket

LED1 to LED4 provide the internal regulated current

source for each of the LED cathodes. These pins enter

high−impedance zero current state whenever the device is

placed in shutdown mode. If an LED pin is directly tied to

VOUT, that channel is disabled.

TAB is the exposed pad underneath the package. For best

thermal performance, the tab should be soldered to the PCB

and connected to the ground plane.

for the LEDs. The voltage at this pin regulated to 0.6 V. The

ground side of the external resistor should be star connected

back to the GND of the PCB. In shutdown mode, RSET

becomes high impedance.