a8435 Allegro MicroSystems, Inc., a8435 Datasheet - Page 3

• Manufacturer Part Number: a8435
• Description: High Efficiency Charge Pump White Led Driver
• Manufacturer: Allegro MicroSystems, Inc.

A8435
Terminal List Table
* See Application Information section for cited figure and tables.
VOUT
Name
CTRL
LED1
LED2
LED3
LED4
GND
ISET
EN1
EN2
C1–
C1+
C2–
C2+
VIN
NC
EP
Pin Number
13
16
15
11
10
12
14
1
4
3
5
–
6
8
7
9
2
Negative terminal of capacitor C1.
Positive terminal of capacitor C1.
Negative terminal of capacitor C2.
Positive terminal of capacitor C2.
Brightness control scheme toggle. For 2-bit parallel or PWM dimming, leave open or tie to VIN
(see table 1). For single-wire serial input dimming, connect to GND (see figure 2).
When CTRL is open or HIGH: Enable and dimming control input 1 (see table 1).
When CTRL is grounded: single-wire enable and dimming control (see table 1 and figure 2).
(Do not leave unconnected.)
When CTRL is open or HIGH: Enable and dimming control input 2 (see table 1).
When CTRL is grounded: this pin disables shutdown. (Do not leave unconnected.)
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 LEDs.
Current sink for LED1. Connect to VIN or VOUT if not used for LED. (Do not leave unconnected.)
Current sink for LED2. Connect to VIN or VOUT if not used for LED. (Do not leave unconnected.)
Current sink for LED3. Always connect this pin to LED.
Current sink for LED4. Connect to VIN or VOUT if not used for LED. (Do not leave unconnected.)
No Connection.
Power supply voltage input.
Charge pump voltage source output for connection to the LED anodes.
High Efficiency Charge Pump White LED Driver
VOUT
CTRL
Pin-out Diagram
EN1
C2+
1
2
3
4
(Top View)
EP
12
11
10
9
Function*
NC
GND
LED3
LED4
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
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