Datasheet AK7864A (Asahi Kasei Microdevices) - 8

[AK7864A]
3. LED driver block analog characteristics
(VDD=3.135~3.465V, Ta=070C unless otherwise specified) Item Min. Typ. Max. Unit Remarks LED drive current range 22 66 mA (note 1) The LED protection circuit 105 150 217.5 mA activation current LED current 60 66 72 mA IREF resistor =4.7k±1% (R/G/B) LED pin voltage=2VDD–3.1V LED current accuracy LED pin voltage=2VDD–3.1V (R/G/B) CONT_R/G/B 100 % 000 86.0 87.5 89.0 % 001 73.5 75 76.5 % 010 60.5 62.5 64.5 % 011 48 50 52 % 100 35.5 37.5 39.5 % 101 23 25 27 % 110 10.5 12.5 14.5 % 111 LED current 2.5 2.5 % Refer to LED Vf dependency LED pin voltage=(2VDD–3.1)V LED Vf 1.1 4.8 V (note 2) Current Consumption 1.1 mA Except LED drive current (note 1) IREF resistance [k] ＝ 66 ÷ [LED drive current [mA]] × 4.7[k]. [LED drive current] is possible to be set to 22mA ~ 66mA. (note 2) In order to keep the normal operation at generation of heat of device, when RGB 3ch simultaneous lighting, the minimum of Vf has restriction. Example: (when 3ch simultaneous lighting with drive current 33mA, as for the minimum of Vf, in 1ch 1.1V and the remaining 2ch are 2.0V) When you use simultaneous lighting, since we can check for you whether LED Vf combination to use of a drive current value are possible, please contact us. (note 3) External load: The total line resistance of CPOUT pin ~ LED anode and LED cathode ~ LED_R/G/G pin must be within 2. (note 4) 50% setting is an upper bound when all channels turn on at the same time. MS1336 - E - 00 8 2012/01