a8434 Allegro MicroSystems, Inc., a8434 Datasheet - Page 3

• Manufacturer Part Number: a8434
• Description: 6-channel High Efficiency Charge Pump White Led Driver
• Manufacturer: Allegro MicroSystems, Inc.

A8434
Terminal List Table
LED1, LED2,
LED3, and LED4
LED5 and LED6
VOUT
Name
ENM
GND
ISET
ENS
C1–
C1+
C2–
C2+
VIN
EP
Number
8, 9, 10,
6 and 7
and 11
13
16
15
12
14
1
4
5
–
3
2
Negative terminal of capacitor C1. Connect capacitor C1 between C1+ and C1–.
Positive terminal of capacitor C1.
Negative terminal of capacitor C2
Positive terminal of capacitor C2. Connect capacitor C2 between C2+ and C2–.
Enable and dimming control input for sub display WLED group.
Enable and dimming control input for main display WLED group.
Exposed metal pad on bottom side. Connect this to ground plane for better thermal performance.
Ground.
Connect RSET resistor to ground to set desired constant current through main and sub WLEDs.
I
Current sink for main display WLEDs. If not used, connect to VOUT, but do not leave open. If left
open, the IC works in 2 × mode.
Current sink for sub display WLEDs. If not used, connect to VOUT, but do not leave open. If left open,
the IC works in 2 × mode.
Power supply voltage input.
Charge pump output voltage for display backlight and flash/torch LED anodes.
Connect a 1 μF capacitor, COUT, between VOUT and GND (see figure 2).
LED(max)
= 220 x 0.6 V / R
6-Channel High Efficiency Charge Pump
VOUT
Pin-out Diagram
ISET
ENS
C2+
SET
1
2
3
4
ES Package
(Top View)
EP
12
10
11
9
GND
LED1
LED2
LED3
Function
115 Northeast Cutoff, Box 15036
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 [phone]
www.allegromicro.com
White LED Driver
3