AK7864A Datasheet, PDF (2/13 Pages) Asahi Kasei Microsystems – 3 channel LED driver with Charge Pump

Block Diagram
CP1
CPO
VDD CPOUT
(3.3V±5%)
CP
CC
CN
Charge
Pump
(VDD2)
LED_R LED_G LED_B
SW
SW
SW
Current
Source R
Current
Source G
Current
Source B
Current
Setting
8 step
[AK7864A]
CONT_B
CONT_G
CONT_R
EN
PDN
VSS
IREF
R 1%
Circuit Block Description
 Charge Pump Circuit
A necessary voltage for LED (Vf 4.8V or less) lighting is generated from the voltage supplied to VDD
pin. Please supply the generated voltage from CPOUT pin to external LED.
 LED Driver Part
This product has 3 channel LED driver to drive RGB constant current. Use the ON/ OFF digital
terminal to control the constant current.
The current setting can be set to 8 levels (100%/87.5%/75%/62.5%/50%/37.5%/25%/12.5%) with
CONT_R/G/B and EN combination. The current of 3 channels are same.
It is possible to light 1ch or 3ch simultaneously. Please set the LED current less than 50% by 3ch
simultaneously.
MS1336 - E - 00
2
2012/01